2.3.1b3 (#1181)

We defer cfs cgroup bandwidth limiting until
CPULimitedHost.configDefault(), and we change
Mininet.stop() to call a new host.unlimit()
method if available.

.github/ISSUE_TEMPLATE

@@ -0,0 +1,20 @@
+<!--
+Mininet uses GitHub issues for bug reports and feature requests only.
+These issues can be viewed at bugs.mininet.org
+
+If you have a question that is not a **bug report** or a **feature request**,
+please use the documentation at docs.mininet.org, the FAQ
+at faq.mininet.org, and the mininet-discuss mailing list.
+
+For bug reports, please fill in the following information in detail,
+and also feel free to include additional information such as debug
+output from mn -v debug, etc.
+-->
+### Expected/Desired Behavior:
+
+### Actual Behavior:
+
+### Detailed Steps to Reproduce the Behavior:
+
+### Additional Information:
+

.github/workflows/code-check.yaml

@@ -0,0 +1,22 @@
+
+name: code-check
+
+on: [push, pull_request]
+
+jobs:
+  code-check:
+    name: Mininet Code Check
+    runs-on: ubuntu-latest
+    steps:
+      - name: Set up Python 3.x
+        uses: actions/setup-python@v2
+        with:
+          python-version: 3.x
+      - name: Check out Mininet source
+        uses: actions/checkout@v2
+      - name: Install Mininet code check dependencies
+        run: |
+          PYTHON=`which python` util/install.sh -n
+          python -m pip install pylint==2.15.7
+      - name: Run code check
+        run:  make codecheck

.github/workflows/run-tests.yaml

@@ -0,0 +1,51 @@
+
+name: mininet-tests
+
+on: [push, pull_request]
+
+jobs:
+  test:
+    name: Mininet Tests
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        os: [ubuntu-22.04, ubuntu-20.04]
+        py: [python3, python2]
+    steps:
+      - name: Check out Mininet source
+        uses: actions/checkout@v3
+      - name: Install Python ${{ matrix.py }}
+        run: sudo apt install ${{ matrix.py }}
+      - name: Install Mininet and base dependencies
+        run: |
+          sudo apt-get update -qq
+          # This seems too slow unfortunately:
+          # sudo apt-get upgrade -y -qq
+          PYTHON=${{ matrix.py }} util/install.sh -nv
+      - name: Disable slow udevd
+        run: sudo systemctl stop systemd-udevd
+             systemd-udevd-kernel.socket
+             systemd-udevd-control.socket
+             || echo "couldn't disable udevd"
+      - name: Sanity test
+        run: |
+          export sudo="sudo env PATH=$PATH"
+          export PYTHON=${{ matrix.py }}
+          # Newer OvS tries OpenFlow15 which crashes ovsc on ubuntu-20.04
+          $sudo mn --switch ovs,protocols=OpenFlow13 --test pingall
+      - name: Install test dependencies
+        run: |
+          sudo apt-get install -qq vlan
+          export PYTHON=${{ matrix.py }}
+          sudo $PYTHON -m pip install pexpect
+          util/install.sh -fw
+      - name: Run core tests
+        run: |
+          export sudo="sudo env PATH=$PATH"
+          export PYTHON=${{ matrix.py }}
+          $sudo $PYTHON mininet/test/runner.py -v
+      - name: Run examples tests
+        run: |
+          export sudo="sudo env PATH=$PATH"
+          export PYTHON=${{ matrix.py }}
+          $sudo $PYTHON examples/test/runner.py -v

.pylint

@@ -16,7 +16,7 @@
 #init-hook=
 
 # Profiled execution.
-profile=no
+#profile=no
 
 # Add <file or directory> to the black list. It should be a base name, not a
 # path. You may set this option multiple times.
@@ -41,24 +41,36 @@ load-plugins=
 # can either give multiple identifier separated by comma (,) or put this option
 # multiple time (only on the command line, not in the configuration file where
 # it should appear only once).
-disable=W0704,C0103,W0231,E1102,W0511,W0142,R0902,R0903,R0904,R0913,R0914,R0801,I0011
+#
+# Note: we may want to re-enable some of these at some point, but many of them
+# are just style issues rather than errors.
+#
+disable=invalid-name, super-init-not-called, fixme,
+        too-many-instance-attributes, too-few-public-methods,
+        too-many-locals, too-many-public-methods, duplicate-code,
+        locally-disabled,
+        useless-object-inheritance, unnecessary-pass, no-else-return,
+        no-else-raise, no-else-continue, super-with-arguments,
+        consider-using-f-string, unspecified-encoding
 
+# bad-continuation, wrong-import-order
 
 [REPORTS]
 
 # Set the output format. Available formats are text, parseable, colorized, msvs
 # (visual studio) and html
 output-format=colorized
+msg-template='{path}:{line}: [{msg_id}({symbol}), {obj}] {msg}'
 
-# Include message's id in outpu
-include-ids=yes
+# Include message's id in output
+# include-ids=yes
 
 # Put messages in a separate file for each module / package specified on the
 # command line instead of printing them on stdout. Reports (if any) will be
 # written in a file name "pylint_global.[txt|html]".
-files-output=no
+# files-output=no
 
-# Tells wether to display a full report or only the messages
+# Tells whether to display a full report or only the messages
 reports=no
 
 # Python expression which should return a note less than 10 (10 is the highes
@@ -70,7 +82,7 @@ evaluation=10.0 - ((float(5 * error + warning + refactor + convention) / stateme
 
 # Add a comment according to your evaluation note. This is used by the global
 # evaluation report (R0004).
-comment=no
+#comment=no
 
 # Enable the report(s) with the given id(s).
 #enable-report=
@@ -92,7 +104,7 @@ comment=no
 [BASIC]
 
 # Required attributes for module, separated by a comma
-required-attributes=
+#required-attributes=
 
 # Regular expression which should only match functions or classes name which do
 # not require a docstring
@@ -108,10 +120,10 @@ const-rgx=(([A-Z_][A-Z0-9_]*)|(__.*__))$
 class-rgx=[A-Z_][a-zA-Z0-9]+$
 
 # Regular expression which should only match correct function names
-function-rgx=[a-z_][a-z0-9_]{2,30}$
+function-rgx=[a-z_][a-z0-9]{2,30}$
 
 # Regular expression which should only match correct method names
-method-rgx=[a-z_][a-z0-9_]{2,30}$
+method-rgx=[a-z_][a-z0-9]{2,30}$
 
 # Regular expression which should only match correct instance attribute names
 attr-rgx=[a-z_][a-z0-9_]{2,30}$
@@ -120,7 +132,7 @@ attr-rgx=[a-z_][a-z0-9_]{2,30}$
 argument-rgx=[a-z_][a-z0-9_]{2,30}$
 
 # Regular expression which should only match correct variable names
-variable-rgx=[a-z_][a-z0-9_]{2,30}$
+variable-rgx=[a-z_][a-z0-9]{2,30}$
 
 # Regular expression which should only match correct list comprehension /
 # generator expression variable names
@@ -133,7 +145,7 @@ good-names=i,j,k,ex,Run,_
 bad-names=foo,bar,baz,toto,tutu,tata
 
 # List of builtins function names that should not be used, separated by a comma
-bad-functions=map,filter,apply,inpu
+#bad-functions=map,filter,apply,inpu
 
 
 # try to find bugs in the code using type inference
@@ -150,7 +162,7 @@ ignored-classes=SQLObjec
 
 # When zope mode is activated, add a predefined set of Zope acquired attributes
 # to generated-members.
-zope=no
+#zope=no
 
 # List of members which are set dynamically and missed by pylint inference
 # system, and so shouldn't trigger E0201 when accessed.
@@ -188,10 +200,10 @@ additional-builtins=
 
 # List of interface methods to ignore, separated by a comma. This is used for
 # instance to not check methods defines in Zope's Interface base class.
-ignore-iface-methods=isImplementedBy,deferred,extends,names,namesAndDescriptions,queryDescriptionFor,getBases,getDescriptionFor,getDoc,getName,getTaggedValue,getTaggedValueTags,isEqualOrExtendedBy,setTaggedValue,isImplementedByInstancesOf,adaptWith,is_implemented_by
+#ignore-iface-methods=isImplementedBy,deferred,extends,names,namesAndDescriptions,queryDescriptionFor,getBases,getDescriptionFor,getDoc,getName,getTaggedValue,getTaggedValueTags,isEqualOrExtendedBy,setTaggedValue,isImplementedByInstancesOf,adaptWith,is_implemented_by
 
 # List of method names used to declare (i.e. assign) instance attributes.
-defining-attr-methods=__init__,__new__,setUp
+defining-attr-methods=__init__,__new__,setUp,build
 
 
 # checks for sign of poor/misdesign:
@@ -210,7 +222,7 @@ max-locals=15
 max-returns=6
 
 # Maximum number of branch for function / method body
-max-branchs=12
+#max-branchs=12
 
 # Maximum number of statements in function / method body
 max-statements=50
@@ -264,7 +276,8 @@ int-import-graph=
 max-line-length=80
 
 # Maximum number of lines in a module
-max-module-lines=1500
+# XXX 1500 -> 4000 for miniedit.py
+max-module-lines=4000
 
 # String used as indentation unit. This is usually " " (4 spaces) or "\t" (1
 # tab).

CONTRIBUTORS

@@ -7,32 +7,74 @@ or send a pull request.
 
 Contributors include:
 
-Mininet Core Team
+Mininet Core Team (and alumni)
 
 Bob Lantz
 Brandon Heller
 Nikhil Handigol
 Vimal Jeyakumar
 Brian O'Connor
+Cody Burkard
 
 Additional Mininet Contributors
 
-Gustavo Pantuza Coelho Pinto
+Joseph Beshay
+M S Vishwanath Bhat
+Muhammad Umair Bhatti
+Arie Bregman
+Tomasz Buchert
+Fernando Cappi
+HW Chiu
 Ryan Cox
 Shaun Crampton
+Jason Croft
+Hantao Cui
+Nirmoy Das
+Lenoardo D'avila
+Giuseppe Di Lena
 David Erickson
+Juan Gascon
 Glen Gibb
 Andrew Ferguson
 Eder Leao Fernandes
+Julian Filter
+Ben Frankel
+Tim Gates
+Gregory Gee
+Jon Hall
+Roan Huang
 Vitaly Ivanov
+Theo Jepsen
+Mathieu Jadin
+Babis Kaidos
 Rich Lane
+Rémy Léone
+Xiaozhou Li
+Zi Shen Lim
+David Mahler
+Felix Maurer
 Murphy McCauley
+Alex Moijes
+Felician Nemeth
 José Pedro Oliveira
 James Page
+Gustavo Pantuza Coelho Pinto
+Ramon Pujianto
+Stempha Reiter
+Damien Saucez
+Shan Sikdar
 Angad Singh
 Piyush Srivastava
 Ed Swierk
+Darshan Thaker
+Olivier Tl]ilmans
+Niels van Adrichem
+Brad Walker
+Andreas Wundsam
+Vikas Yadav
 Isaku Yamahata
+Baohua Yang
+Zhuo
 
 Thanks also to everyone who has submitted issues and pull
 requests on github, and to our friendly mininet-discuss

INSTALL

@@ -2,7 +2,7 @@
 Mininet Installation/Configuration Notes
 ----------------------------------------
 
-Mininet 2.1.0+
+Mininet 2.3.1b3
 ---
 
 The supported installation methods for Mininet are 1) using a
@@ -32,68 +32,112 @@ like to contribute an installation script, we would welcome it!)
 2. Next-easiest option: use our Ubuntu package!
 
    To install Mininet itself (i.e. `mn` and the Python API) on Ubuntu
-   12.10+:
+   16.04+:
 
         sudo apt-get install mininet
 
-   Note: if you are upgrading from an older version of Mininet, make
-   sure you remove the old OVS from `/usr/local`:
-
-        sudo rm /usr/local/bin/ovs*
-        sudo rm /usr/local/sbin/ovs*
+   Note: this may install an older version of Mininet which may not
+   support Python 3. If you would like the latest version of Mininet,
+   consider installing from source as described in the next section.
 
 3. Native installation from source
 
-3.1. Native installation from source on Ubuntu 12.04+
+   If you are running Ubuntu, Debian, or Fedora, you may be able to use
+   our handy `install.sh` script, which is in `util/`. Please read the
+   following sections first.
+
+3.1. Obtaining the Mininet source code
 
    If you're reading this, you've probably already done so, but the
    command to download the Mininet source code is:
 
-        git clone git://github.com/mininet/mininet.git
+        git clone https://github.com/mininet/mininet.git
 
    Note that the above git command will check out the latest and greatest
-   Mininet (which we recommend!) If you want to run the last tagged/released
-   version of Mininet, use:
+   Mininet (which we recommend!) If you want to run the last
+   tagged/released version of Mininet, you can look at the release tags
+   using
 
-        git clone git://github.com/mininet/mininet
-        git checkout -b 2.1.0 2.1.0
+        cd mininet
+        git tag
 
-   If you are running Ubuntu, you may be able to use our handy
-   `install.sh` script, which is in `mininet/util`.
+    and then
 
-   *WARNING: USE AT YOUR OWN RISK!*
+        git checkout <release tag>
 
-   `install.sh` is a bit intrusive and may possibly damage your OS
+   where <release tag> is the release you want to check out.
+
+3.1.1 *CAUTION: USE AT YOUR OWN RISK!*
+
+   `install.sh` can be a bit intrusive and may possibly damage your OS
    and/or home directory, by creating/modifying several directories
-   such as `mininet`, `openflow`, `oftest`, `pox`, etc..
+   such as `mininet`, `openflow`, `oftest`, `pox`, etc.. We recommend
+   trying it in a VM before trying it on a system you use from day to
+   day.
+
    Although we hope it won't do anything completely terrible, you may
    want to look at the script before you run it, and you should make
    sure your system and home directory are backed up just in case!
 
-   To install Mininet itself, the OpenFlow reference implementation, and
+   You can change the directory where the dependencies are installed
+   using the -s <directory> flag.
+
+        util/install.sh -s <directory> ...
+
+3.1.2 Running `install.sh`
+
+   Installing a "minimal" version of Mininet with Open vSwitch should
+   be reasonably non-perturbing since it should not create directories
+   for other tools:
+
+       util/install.sh -nv
+
+   Note this will not install a controller, so you will have to either
+   install your own controller, or use a switch such OVSBridge that does
+   not require a controller:
+
+       sudo mn --switch ovsbr --test pingall
+
+   To install Mininet itself, the OpenFlow reference controller, and
    Open vSwitch, you may use:
 
-        mininet/util/install.sh -fnv
+        util/install.sh -fnv
 
    This should be reasonably quick, and the following command should
    work after the installation:
 
         sudo mn --test pingall
 
+3.1.3 Python 3 and Python 2 support
+
+   Mininet supports Python 3 and Python 2. By default, `install.sh`
+   will use whatever `python` is on your system.  To specify a
+   specific version of Pythonm, you can set the PYTHON environment
+   variable:
+
+       PYTHON=python3 util/install.sh -fnv
+
+   You can install Mininet for both Python 3 and Python 2:
+
+       PYTHON=python2 util/install.sh -fnv
+       PYTHON=python3 util/install.sh -n
+
+   Whichever version was installed last will be the default for `mn`.
+   As long as Mininet is installed for the appropriate version of
+   Python, you can run it using that version of Python:
+
+       python3 `which mn`
+       python2 `which mn`
+
    To install ALL of the software which we use for OpenFlow tutorials,
    including POX, the OpenFlow WireShark dissector, the `oftest`
    framework, and other potentially useful software, you may use:
 
-        mininet/util/install.sh -a
+        util/install.sh -a
 
    This takes about 4 minutes on our test system.
 
-   You can change the directory where the dependencies are installed using
-   the -s <directory> flag.
-
-        mininet/util/install.sh -s <directory> -a
-
-3.2. Native installation from source on Fedora 18+.
+3.2. (Experimental) Native installation from source on Fedora:
 
    As root execute the following operations:
 
@@ -101,26 +145,14 @@ like to contribute an installation script, we would welcome it!)
 
         yum install git
 
-    * create an user account (e.g. mininet) and add it to the wheel group
-
-        useradd [...] mininet
-        usermod -a -G wheel mininet
-
-    * change the SElinux setting to permissive. It can be done
-      temporarily with:
-
-        setenforce 0
-
-   then login with the new account (e.g. mininet) and do the following:
-
     * clone the Mininet repository
 
-        git clone git://github.com/mininet/mininet.git
+        git clone https://github.com/mininet/mininet.git
 
     * install Mininet, the OpenFlow reference implementation, and
       Open vSwitch
 
-        mininet/util/install.sh -fnv
+        util/install.sh -fnv
 
     * enable and start openvswitch
 
@@ -131,7 +163,10 @@ like to contribute an installation script, we would welcome it!)
 
         sudo mn --test pingall
 
-4. Creating your own Mininet/OpenFlow tutorial VM
+    Note that `install.sh -fnv `may not install all dependencies on Fedora,
+    and many tests may still fail.
+
+4. Creating your own Mininet/OpenFlow tutorial VM on Ubuntu/Debian
 
    Creating your own Ubuntu Mininet VM for use with the OpenFlow tutorial
    is easy! First, create a new Ubuntu VM. Next, run two commands in it:
@@ -147,16 +182,15 @@ like to contribute an installation script, we would welcome it!)
 
    Although we don't support other Linux distributions directly, it
    should be possible to install and run Mininet with some degree of
-   manual effort.
+   manual effort. People have even gotten `mn --switch user` to run
+   in a ChromeOS container.
 
    In general, you must have:
 
    * A Linux kernel compiled with network namespace support enabled
 
-   * An OpenFlow implementation (either the reference user or kernel
-     space implementations, or Open vSwitch.) Appropriate kernel
-     modules (e.g. tun and ofdatapath for the reference kernel
-     implementation) must be loaded.
+   * An compatible software switch such as Open vSwitch or
+     the Linux bridge.
 
    * Python, `bash`, `ping`, `iperf`, etc.
 
@@ -166,8 +200,11 @@ like to contribute an installation script, we would welcome it!)
    support other Linux distributions.
 
 
-Good luck!
+As always, please feel free to submit issues or pull requests for
+installation-related features.
 
-Mininet Team
+Good luck, and have fun!
+
+Mininet Developers
 
 ---

LICENSE

@@ -1,33 +1,29 @@
-Mininet 2.1.0+ License
+BSD 3-Clause License (original Mininet authors: Bob Lantz and Brandon Heller)
 
-Copyright (c) 2013 Open Networking Laboratory
-Copyright (c) 2009-2012 Bob Lantz and The Board of Trustees of
-The Leland Stanford Junior University
+Copyright (c) 2013-2022 Open Networking Foundation
+Copyright (c) 2009-2012 Bob Lantz and The Board of Trustees of The Leland Stanford Junior University
 
-Original authors: Bob Lantz and Brandon Heller
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
 
-We are making Mininet available for public use and benefit with the
-expectation that others will use, modify and enhance the Software and
-contribute those enhancements back to the community. However, since we
-would like to make the Software available for broadest use, with as few
-restrictions as possible permission is hereby granted, free of charge, to
-any person obtaining a copy of this Software to deal in the Software
-under the copyrights without restriction, including without limitation
-the rights to use, copy, modify, merge, publish, distribute, sublicense,
-and/or sell copies of the Software, and to permit persons to whom the
-Software is furnished to do so, subject to the following conditions:
+1. Redistributions of source code must retain the above copyright notice, this
+   list of conditions and the following disclaimer.
 
-The above copyright notice and this permission notice shall be included
-in all copies or substantial portions of the Software.
+2. Redistributions in binary form must reproduce the above copyright notice,
+   this list of conditions and the following disclaimer in the documentation
+   and/or other materials provided with the distribution.
 
-THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
-OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
-MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
-IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
-CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
-TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
-SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+3. Neither the name of the copyright holder nor the names of its
+   contributors may be used to endorse or promote products derived from
+   this software without specific prior written permission.
 
-The name and trademarks of copyright holder(s) may NOT be used in
-advertising or publicity pertaining to the Software or any derivatives
-without specific, written prior permission.
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

Makefile

@@ -2,15 +2,19 @@ MININET = mininet/*.py
 TEST = mininet/test/*.py
 EXAMPLES = mininet/examples/*.py
 MN = bin/mn
+PYTHON ?= python
+PYMN = $(PYTHON) -B bin/mn
 BIN = $(MN)
 PYSRC = $(MININET) $(TEST) $(EXAMPLES) $(BIN)
 MNEXEC = mnexec
 MANPAGES = mn.1 mnexec.1
-P8IGN = E251,E201,E302,E202
-BINDIR = /usr/bin
-MANDIR = /usr/share/man/man1
+P8IGN = E251,E201,E302,E202,E126,E127,E203,E226,E402,W504,W503,E731
+PREFIX ?= /usr
+BINDIR ?= $(PREFIX)/bin
+MANDIR ?= $(PREFIX)/share/man/man1
 DOCDIRS = doc/html doc/latex
 PDF = doc/latex/refman.pdf
+CC ?= cc
 
 CFLAGS += -Wall -Wextra
 
@@ -22,13 +26,14 @@ clean:
 codecheck: $(PYSRC)
 	-echo "Running code check"
 	util/versioncheck.py
-	pyflakes $(PYSRC)
+	pyflakes3 $(PYSRC) || pyflakes $(PYSRC)
 	pylint --rcfile=.pylint $(PYSRC)
-	pep8 --repeat --ignore=$(P8IGN) $(PYSRC)
+#	Exclude miniedit from pep8 checking for now
+	pep8 --repeat --ignore=$(P8IGN) `ls $(PYSRC) | grep -v miniedit.py`
 
 errcheck: $(PYSRC)
 	-echo "Running check for errors only"
-	pyflakes $(PYSRC)
+	pyflakes3 $(PYSRC) || pyflakes $(PYSRC)
 	pylint -E --rcfile=.pylint $(PYSRC)
 
 test: $(MININET) $(TEST)
@@ -36,29 +41,42 @@ test: $(MININET) $(TEST)
 	mininet/test/test_nets.py
 	mininet/test/test_hifi.py
 
-mnexec: mnexec.c $(MN) mininet/net.py
-	cc $(CFLAGS) $(LDFLAGS) -DVERSION=\"`PYTHONPATH=. $(MN) --version`\" $< -o $@
+slowtest: $(MININET)
+	-echo "Running slower tests (walkthrough, examples)"
+	mininet/test/test_walkthrough.py -v
+	mininet/examples/test/runner.py -v
 
-install: $(MNEXEC) $(MANPAGES)
-	install $(MNEXEC) $(BINDIR)
-	install $(MANPAGES) $(MANDIR)
-	python setup.py install
+mnexec: mnexec.c $(MN) mininet/net.py
+	$(CC) $(CFLAGS) $(LDFLAGS) \
+	-DVERSION=\"`PYTHONPATH=. $(PYMN) --version 2>&1`\" $< -o $@
+
+install-mnexec: $(MNEXEC)
+	install -D $(MNEXEC) $(BINDIR)/$(MNEXEC)
+
+install-manpages: $(MANPAGES)
+	install -D -t $(MANDIR) $(MANPAGES)
+
+install: install-mnexec install-manpages
+#	This seems to work on all pip versions
+	$(PYTHON) -m pip uninstall -y mininet || true
+	$(PYTHON) -m pip install .
 
 develop: $(MNEXEC) $(MANPAGES)
-	# Perhaps we should link these as well
+# 	Perhaps we should link these as well
 	install $(MNEXEC) $(BINDIR)
 	install $(MANPAGES) $(MANDIR)
-	python setup.py develop
+	$(PYTHON) -m pip uninstall -y mininet || true
+	$(PYTHON) -m pip install -e . --no-binary :all:
 
 man: $(MANPAGES)
 
 mn.1: $(MN)
 	PYTHONPATH=. help2man -N -n "create a Mininet network." \
-	--no-discard-stderr $< -o $@
+	--no-discard-stderr "$(PYMN)" -o $@
 
 mnexec.1: mnexec
 	help2man -N -n "execution utility for Mininet." \
-	-h "-h" -v "-v" --no-discard-stderr ./$< -o $@ 
+	-h "-h" -v "-v" --no-discard-stderr ./$< -o $@
 
 .PHONY: doc
 

README.md

@@ -1,9 +1,11 @@
 Mininet: Rapid Prototyping for Software Defined Networks
 ========================================================
-
 *The best way to emulate almost any network on your laptop!*
 
-Version 2.1.0+
+Mininet 2.3.1b3
+
+[![Build Status][1]](https://github.com/mininet/mininet/actions)
+
 
 ### What is Mininet?
 
@@ -66,32 +68,35 @@ Mininet includes:
 
   `mn -c`
 
-### New features in 2.1.0+
+### Python 3 Support
 
-Mininet 2.1.0+ provides a number of bug fixes as well as
-several new features, including:
+- Mininet 2.3.1b3 supports Python 3 and Python 2
 
-* Convenient access to `Mininet()` as a dict of nodes
-* X11 tunneling (wireshark in Mininet hosts, finally!)
-* Accurate reflection of the `Mininet()` object in the CLI
-* Automatically detecting and adjusting resource limits
-* Automatic cleanup on failure of the `mn` command
-* Preliminary support for running OVS in user space mode
-* Preliminary support (`IVSSwitch()`) for the Indigo Virtual Switch
-* support for installing the OpenFlow 1.3 versions of the reference
-  user switch and NOX from CPqD
-* The ability to import modules from `mininet.examples`
+- You can install both the Python 3 and Python 2 versions of
+Mininet side by side, but the most recent installation will
+determine which Python version is used by default by `mn`.
 
-We have provided several new examples (which can easily be
-imported to provide useful functionality) including:
+- You can run `mn` directly with Python 2 or Python 3,
+  as long as the appropriate version of Mininet is installed,
+  e.g.
 
-* Modeling separate control and data networks: `mininet.examples.controlnet`
-* Connecting Mininet hosts the internet (or a LAN) using NAT: `mininet.examples.nat`
-* Creating per-host custom directories using bind mounts: `mininet.examples.bind`
+      $ sudo python2 `which mn`
 
-Note that examples contain experimental features which might
-"graduate" into mainline Mininet in the future, but they should 
-not be considered a stable part of the Mininet API!
+- More information regarding Python 3 and Python 2 support
+  may be found in the release notes on http://docs.mininet.org.
+
+### Other Enhancements and Information
+
+- Support for Ubuntu 22.04 LTS (and 20.04)
+
+- More reliable testing and CI via github actions
+
+- Preliminary support for cgroups v2 (and v1)
+
+- Minor bug fixes (2.3.1)
+
+- Additional information about this release and previous releases
+  may be found in the release notes on http://docs.mininet.org.
 
 ### Installation
 
@@ -104,7 +109,8 @@ information, including a Mininet walkthrough and an introduction
 to the Python API, is available on the
 [Mininet Web Site](http://mininet.org).
 There is also a wiki which you are encouraged to read and to
-contribute to, particularly the Frequently Asked Questions (FAQ.)
+contribute to, particularly the Frequently Asked Questions
+(FAQ) at http://faq.mininet.org.
 
 ### Support
 
@@ -113,21 +119,24 @@ Mininet mailing list, `mininet-discuss` at:
 
 <https://mailman.stanford.edu/mailman/listinfo/mininet-discuss>
 
-### Contributing
+### Join Us
+
+Thanks again to all of the Mininet contributors and users!
 
 Mininet is an open source project and is currently hosted
-at <https://github.com/mininet>.  You are encouraged to download
-the code, examine it, modify it, and submit bug reports, bug fixes,
-feature requests, new features and other issues and pull requests.
-Thanks to everyone who has contributed to the project
-(see CONTRIBUTORS for more info!)
+at <https://github.com/mininet>. You are encouraged to download,
+examine, and modify the code, and to submit bug reports, bug fixes,
+feature requests, new features, and other issues and pull requests.
+Thanks to everyone who has contributed code to the Mininet project
+(see CONTRIBUTORS for more info!) It is because of everyone's
+hard work that Mininet continues to grow and improve.
 
-Best wishes, and we look forward to seeing what you can do with
-Mininet to change the networking world!
+### Enjoy Mininet
 
-### Credits
+Have fun! We look forward to seeing what you will do with Mininet
+to change the networking world.
 
-The Mininet 2.1.0+ Team:
+Bob Lantz,
+on behalf of the Mininet Contributors
 
-* Bob Lantz
-* Brian O'Connor
+[1]: https://github.com/mininet/mininet/workflows/mininet-tests/badge.svg

bin/mn

@@ -11,111 +11,153 @@ Example to pull custom params (topo, switch, etc.) from a file:
   sudo mn --custom ~/mininet/custom/custom_example.py
 """
 
-from optparse import OptionParser
 import os
 import sys
 import time
 
+from functools import partial
+from optparse import OptionParser  # pylint: disable=deprecated-module
+from sys import exit  # pylint: disable=redefined-builtin
+
 # Fix setuptools' evil madness, and open up (more?) security holes
 if 'PYTHONPATH' in os.environ:
     sys.path = os.environ[ 'PYTHONPATH' ].split( ':' ) + sys.path
 
+# pylint: disable=wrong-import-position
+
 from mininet.clean import cleanup
-from mininet.cli import CLI
-from mininet.log import lg, LEVELS, info, debug, warn, error
+import mininet.cli
+from mininet.log import lg, LEVELS, info, debug, warn, error, output
 from mininet.net import Mininet, MininetWithControlNet, VERSION
 from mininet.node import ( Host, CPULimitedHost, Controller, OVSController,
-                           RYU, NOX, RemoteController, DefaultController,
-                           UserSwitch, OVSSwitch,
-                           OVSLegacyKernelSwitch, IVSSwitch )
+                           Ryu, NOX, RemoteController, findController,
+                           DefaultController, NullController,
+                           UserSwitch, OVSSwitch, OVSBridge,
+                           IVSSwitch )
 from mininet.nodelib import LinuxBridge
-from mininet.link import Link, TCLink
-from mininet.topo import SingleSwitchTopo, LinearTopo, SingleSwitchReversedTopo
+from mininet.link import Link, TCLink, TCULink, OVSLink
+from mininet.topo import ( SingleSwitchTopo, LinearTopo,
+                           SingleSwitchReversedTopo, MinimalTopo )
 from mininet.topolib import TreeTopo, TorusTopo
-from mininet.util import custom, customConstructor
-from mininet.util import buildTopo
-
-from functools import partial
+from mininet.util import customClass, specialClass, splitArgs, buildTopo
 
 # Experimental! cluster edition prototype
 from mininet.examples.cluster import ( MininetCluster, RemoteHost,
                                        RemoteOVSSwitch, RemoteLink,
-                                       SwitchBinPlacer, RandomPlacer )
-from mininet.examples.clustercli import DemoCLI as ClusterCLI
+                                       SwitchBinPlacer, RandomPlacer,
+                                       ClusterCleanup )
+from mininet.examples.clustercli import ClusterCLI
+
 
 PLACEMENT = { 'block': SwitchBinPlacer, 'random': RandomPlacer }
 
 # built in topologies, created only when run
 TOPODEF = 'minimal'
-TOPOS = { 'minimal': lambda: SingleSwitchTopo( k=2 ),
+TOPOS = { 'minimal': MinimalTopo,
           'linear': LinearTopo,
           'reversed': SingleSwitchReversedTopo,
           'single': SingleSwitchTopo,
           'tree': TreeTopo,
           'torus': TorusTopo }
 
-SWITCHDEF = 'ovsk'
+SWITCHDEF = 'default'
 SWITCHES = { 'user': UserSwitch,
-             'ovs':  OVSSwitch,
+             'ovs': OVSSwitch,
+             'ovsbr' : OVSBridge,
              # Keep ovsk for compatibility with 2.0
              'ovsk': OVSSwitch,
-             'ovsl': OVSLegacyKernelSwitch,
              'ivs': IVSSwitch,
-             'lxbr': LinuxBridge }
+             'lxbr': LinuxBridge,
+             'default': OVSSwitch }
 
 HOSTDEF = 'proc'
 HOSTS = { 'proc': Host,
-          'rt': custom( CPULimitedHost, sched='rt' ),
-          'cfs': custom( CPULimitedHost, sched='cfs' ) }
+          'rt': specialClass( CPULimitedHost, defaults=dict( sched='rt' ) ),
+          'cfs': specialClass( CPULimitedHost, defaults=dict( sched='cfs' ) ) }
 
 CONTROLLERDEF = 'default'
 CONTROLLERS = { 'ref': Controller,
                 'ovsc': OVSController,
                 'nox': NOX,
                 'remote': RemoteController,
-                'default': DefaultController,
-                'ryu': RYU,
-                'none': lambda name: None }
+                'ryu': Ryu,
+                'default': DefaultController,  # Note: overridden below
+                'none': NullController }
 
 LINKDEF = 'default'
-LINKS = { 'default': Link,
-          'tc': TCLink }
+LINKS = { 'default': Link,  # Note: overridden below
+          'tc': TCLink,
+          'tcu': TCULink,
+          'ovs': OVSLink }
+
+# TESTS dict can contain functions and/or Mininet() method names
+# XXX: it would be nice if we could specify a default test, but
+# this may be tricky
+TESTS = { name: True
+          for name in ( 'pingall', 'pingpair', 'iperf', 'iperfudp' ) }
+
+CLI = None  # Set below if needed
+
+# Locally defined tests
+def allTest( net ):
+    "Run ping and iperf tests"
+    net.start()
+    net.ping()
+    net.iperf()
+
+def nullTest( _net ):
+    "Null 'test' (does nothing)"
+    pass
 
 
-# optional tests to run
-TESTS = [ 'cli', 'build', 'pingall', 'pingpair', 'iperf', 'all', 'iperfudp',
-          'none' ]
+TESTS.update( all=allTest, none=nullTest, build=nullTest )
 
-ALTSPELLING = { 'pingall': 'pingAll',
-                'pingpair': 'pingPair',
-                'iperfudp': 'iperfUdp',
-                'iperfUDP': 'iperfUdp' }
+# Map to alternate spellings of Mininet() methods
+ALTSPELLING = { 'pingall': 'pingAll', 'pingpair': 'pingPair',
+                'iperfudp': 'iperfUdp' }
+
+def runTests( mn, options ):
+    """Run tests
+       mn: Mininet object
+       option: list of test optinos """
+    # Split option into test name and parameters
+    for option in options:
+        # Multiple tests may be separated by '+' for now
+        for test in option.split( '+' ):
+            test, args, kwargs = splitArgs( test )
+            test = ALTSPELLING.get( test.lower(), test )
+            testfn = TESTS.get( test, test )
+            if callable( testfn ):
+                testfn( mn, *args, **kwargs )
+            elif hasattr( mn, test ):
+                getattr( mn, test )( *args, **kwargs )
+            else:
+                raise Exception( 'Test %s is unknown - please specify one of '
+                                 '%s ' % ( test, TESTS.keys() ) )
 
 
-def addDictOption( opts, choicesDict, default, name, helpStr=None ):
+def addDictOption( opts, choicesDict, default, name, **kwargs ):
     """Convenience function to add choices dicts to OptionParser.
        opts: OptionParser instance
        choicesDict: dictionary of valid choices, must include default
        default: default choice key
        name: long option name
-       help: string"""
-    if default not in choicesDict:
-        raise Exception( 'Invalid  default %s for choices dict: %s' %
-                         ( default, name ) )
-    if not helpStr:
-        helpStr = ( '|'.join( sorted( choicesDict.keys() ) ) +
-                    '[,param=value...]' )
-    opts.add_option( '--' + name,
-                     type='string',
-                     default = default,
-                     help = helpStr )
-
+       kwargs: additional arguments to add_option"""
+    helpStr = ( '|'.join( sorted( choicesDict.keys() ) ) +
+                '[,param=value...]' )
+    helpList = [ '%s=%s' % ( k, v.__name__ )
+                 for k, v in choicesDict.items() ]
+    helpStr += ' ' + ( ' '.join( helpList ) )
+    params = dict( type='string', default=default, help=helpStr )
+    params.update( **kwargs )
+    opts.add_option( '--' + name, **params )
 
 def version( *_args ):
     "Print Mininet version and exit"
-    print "%s" % VERSION
+    output( "%s\n" % VERSION )
     exit()
 
+
 class MininetRunner( object ):
     "Build, setup, and run Mininet."
 
@@ -129,9 +171,36 @@ class MininetRunner( object ):
         self.setup()
         self.begin()
 
+    def custom( self, _option, _opt_str, value, _parser ):
+        """Parse custom file and add params.
+           option: option e.g. --custom
+           opt_str: option string e.g. --custom
+           value: the value the follows the option
+           parser: option parser instance"""
+        files = []
+        if os.path.isfile( value ):
+            # Accept any single file (including those with commas)
+            files.append( value )
+        else:
+            # Accept a comma-separated list of filenames
+            files += value.split(',')
+
+        for fileName in files:
+            customs = {}
+            if os.path.isfile( fileName ):
+                # pylint: disable=exec-used
+                with open( fileName ) as f:
+                    exec( compile( f.read(), fileName, 'exec' ),
+                          customs, customs )
+                for name, val in customs.items():
+                    self.setCustom( name, val )
+            else:
+                raise Exception( 'could not find custom file: %s' % fileName )
+
     def setCustom( self, name, value ):
         "Set custom parameters for MininetRunner."
-        if name in ( 'topos', 'switches', 'hosts', 'controllers' ):
+        if name in ( 'topos', 'switches', 'hosts', 'controllers', 'links'
+                     'testnames', 'tests' ):
             # Update dictionaries
             param = name.upper()
             globals()[ param ].update( value )
@@ -142,26 +211,23 @@ class MininetRunner( object ):
             # Add or modify global variable or class
             globals()[ name ] = value
 
-    def parseCustomFile( self, fileName ):
-        "Parse custom file and add params before parsing cmd-line options."
-        customs = {}
-        if os.path.isfile( fileName ):
-            execfile( fileName, customs, customs )
-            for name, val in customs.iteritems():
-                self.setCustom( name, val )
+    def setNat( self, _option, opt_str, value, parser ):
+        "Set NAT option(s)"
+        assert self  # satisfy pylint
+        parser.values.nat = True
+        # first arg, first char != '-'
+        if parser.rargs and parser.rargs[ 0 ][ 0 ] != '-':
+            value = parser.rargs.pop( 0 )
+            _, args, kwargs = splitArgs( opt_str + ',' + value )
+            parser.values.nat_args = args
+            parser.values.nat_kwargs = kwargs
         else:
-            raise Exception( 'could not find custom file: %s' % fileName )
+            parser.values.nat_args = []
+            parser.values.nat_kwargs = {}
 
     def parseArgs( self ):
         """Parse command-line args and return options object.
            returns: opts parse options dict"""
-        if '--custom' in sys.argv:
-            index = sys.argv.index( '--custom' )
-            if len( sys.argv ) > index + 1:
-                filename = sys.argv[ index + 1 ]
-                self.parseCustomFile( filename )
-            else:
-                raise Exception( 'Custom file name not found' )
 
         desc = ( "The %prog utility creates Mininet network from the\n"
                  "command line. It can create parametrized topologies,\n"
@@ -173,18 +239,19 @@ class MininetRunner( object ):
         opts = OptionParser( description=desc, usage=usage )
         addDictOption( opts, SWITCHES, SWITCHDEF, 'switch' )
         addDictOption( opts, HOSTS, HOSTDEF, 'host' )
-        addDictOption( opts, CONTROLLERS, CONTROLLERDEF, 'controller' )
+        addDictOption( opts, CONTROLLERS, [], 'controller', action='append' )
         addDictOption( opts, LINKS, LINKDEF, 'link' )
         addDictOption( opts, TOPOS, TOPODEF, 'topo' )
 
         opts.add_option( '--clean', '-c', action='store_true',
                          default=False, help='clean and exit' )
-        opts.add_option( '--custom', type='string', default=None,
-                         help='read custom topo and node params from .py' +
-                         'file' )
-        opts.add_option( '--test', type='choice', choices=TESTS,
-                         default=TESTS[ 0 ],
-                         help='|'.join( TESTS ) )
+        opts.add_option( '--custom', action='callback',
+                         callback=self.custom,
+                         type='string',
+                         help='read custom classes or params from .py file(s)'
+                         )
+        opts.add_option( '--test', default=[], action='append',
+                         dest='test', help='|'.join( TESTS.keys() ) )
         opts.add_option( '--xterms', '-x', action='store_true',
                          default=False, help='spawn xterms for each node' )
         opts.add_option( '--ipbase', '-i', type='string', default='10.0.0.0/8',
@@ -194,11 +261,11 @@ class MininetRunner( object ):
         opts.add_option( '--arp', action='store_true',
                          default=False, help='set all-pairs ARP entries' )
         opts.add_option( '--verbosity', '-v', type='choice',
-                         choices=LEVELS.keys(), default = 'info',
+                         choices=list( LEVELS.keys() ), default = 'info',
                          help = '|'.join( LEVELS.keys() )  )
         opts.add_option( '--innamespace', action='store_true',
                          default=False, help='sw and ctrl in namespace?' )
-        opts.add_option( '--listenport', type='int', default=6634,
+        opts.add_option( '--listenport', type='int', default=6654,
                          help='base port for passive switch listening' )
         opts.add_option( '--nolistenport', action='store_true',
                          default=False, help="don't use passive listening " +
@@ -210,15 +277,26 @@ class MininetRunner( object ):
         opts.add_option( '--pin', action='store_true',
                          default=False, help="pin hosts to CPU cores "
                          "(requires --host cfs or --host rt)" )
-        opts.add_option( '--nat', action='store_true',
-                         default=False, help="adds a NAT to the topology "
-                         "that connects Mininet to the physical network" )
-        opts.add_option( '--version', action='callback', callback=version )
+        opts.add_option( '--nat', action='callback', callback=self.setNat,
+                         help="[option=val...] adds a NAT to the topology that"
+                         " connects Mininet hosts to the physical network."
+                         " Warning: This may route any traffic on the machine"
+                         " that uses Mininet's"
+                         " IP subnet into the Mininet network."
+                         " If you need to change"
+                         " Mininet's IP subnet, see the --ipbase option." )
+        opts.add_option( '--version', action='callback', callback=version,
+                         help='prints the version and exits' )
+        opts.add_option( '--wait', '-w', action='store_true',
+                         default=False, help='wait for switches to connect' )
+        opts.add_option( '--twait', '-t', action='store', type='int',
+                         dest='wait',
+                         help='timed wait (s) for switches to connect' )
         opts.add_option( '--cluster', type='string', default=None,
                          metavar='server1,server2...',
                          help=( 'run on multiple servers (experimental!)' ) )
         opts.add_option( '--placement', type='choice',
-                         choices=PLACEMENT.keys(), default='block',
+                         choices=list( PLACEMENT.keys() ), default='block',
                          metavar='block|random',
                          help=( 'node placement for --cluster '
                                 '(experimental!) ' ) )
@@ -235,92 +313,116 @@ class MininetRunner( object ):
 
         # set logging verbosity
         if LEVELS[self.options.verbosity] > LEVELS['output']:
-            print ( '*** WARNING: selected verbosity level (%s) will hide CLI '
+            warn( '*** WARNING: selected verbosity level (%s) will hide CLI '
                     'output!\n'
-                    'Please restart Mininet with -v [debug, info, output].'
+                    'Please restart Mininet with -v [debug, info, output].\n'
                     % self.options.verbosity )
         lg.setLogLevel( self.options.verbosity )
 
+    # Maybe we'll reorganize this someday...
+    # pylint: disable=too-many-branches,too-many-statements,global-statement
+
     def begin( self ):
         "Create and run mininet."
 
         global CLI
-        
-        if self.options.clean:
+
+        opts = self.options
+
+        if opts.cluster:
+            servers = opts.cluster.split( ',' )
+            for server in servers:
+                ClusterCleanup.add( server )
+
+        if opts.clean:
             cleanup()
             exit()
 
         start = time.time()
 
-        topo = buildTopo( TOPOS, self.options.topo )
-        switch = customConstructor( SWITCHES, self.options.switch )
-        host = customConstructor( HOSTS, self.options.host )
-        controller = customConstructor( CONTROLLERS, self.options.controller )
-        link = customConstructor( LINKS, self.options.link )
+        if not opts.controller:
+            # Update default based on available controllers
+            CONTROLLERS[ 'default' ] = findController()
+            opts.controller = [ 'default' ]
+            if not CONTROLLERS[ 'default' ]:
+                opts.controller = [ 'none' ]
+                if opts.switch == 'default':
+                    info( '*** No default OpenFlow controller found '
+                          'for default switch!\n' )
+                    info( '*** Falling back to OVS Bridge\n' )
+                    opts.switch = 'ovsbr'
+                elif opts.switch not in ( 'ovsbr', 'lxbr' ):
+                    raise Exception( "Could not find a default controller "
+                                     "for switch %s" %
+                                     opts.switch )
+
+        topo = buildTopo( TOPOS, opts.topo )
+        switch = customClass( SWITCHES, opts.switch )
+        host = customClass( HOSTS, opts.host )
+        controller = [ customClass( CONTROLLERS, c )
+                       for c in opts.controller ]
+
+        if opts.switch == 'user' and opts.link == 'default':
+            debug( '*** Using TCULink with UserSwitch\n' )
+            # Use link configured correctly for UserSwitch
+            opts.link = 'tcu'
+
+        link = customClass( LINKS, opts.link )
 
         if self.validate:
-            self.validate( self.options )
+            self.validate( opts )
 
-        ipBase = self.options.ipbase
-        xterms = self.options.xterms
-        mac = self.options.mac
-        arp = self.options.arp
-        pin = self.options.pin
-        listenPort = None
-        if not self.options.nolistenport:
-            listenPort = self.options.listenport
+        if opts.nolistenport:
+            opts.listenport = None
 
-        # Handle inNamespace, cluster options
-        inNamespace = self.options.innamespace
-        cluster = self.options.cluster
-        if inNamespace and cluster:
-            print "Please specify --innamespace OR --cluster"
+        # Handle innamespace, cluster options
+        if opts.innamespace and opts.cluster:
+            error( "Please specify --innamespace OR --cluster\n" )
             exit()
-        Net = MininetWithControlNet if inNamespace else Mininet
-        if cluster:
+        Net = MininetWithControlNet if opts.innamespace else Mininet
+        if opts.cluster:
             warn( '*** WARNING: Experimental cluster mode!\n'
-              '*** Using RemoteHost, RemoteOVSSwitch, RemoteLink\n' )
+                  '*** Using RemoteHost, RemoteOVSSwitch, RemoteLink\n' )
             host, switch, link = RemoteHost, RemoteOVSSwitch, RemoteLink
-            CLI = ClusterCLI
-            Net = partial( MininetCluster, servers=cluster.split( ',' ),
-                           placement=PLACEMENT[ self.options.placement ] )
+            Net = partial( MininetCluster, servers=servers,
+                           placement=PLACEMENT[ opts.placement ] )
+            mininet.cli.CLI = ClusterCLI
+
+        # Wait for controllers to connect unless we're running null test
+        if ( opts.test and opts.test != [ 'none' ] and
+             isinstance( opts.wait, bool ) ):
+            opts.wait = True
 
         mn = Net( topo=topo,
-                  switch=switch, host=host, controller=controller,
-                  link=link,
-                  ipBase=ipBase,
-                  inNamespace=inNamespace,
-                  xterms=xterms, autoSetMacs=mac,
-                  autoStaticArp=arp, autoPinCpus=pin,
-                  listenPort=listenPort )
+                  switch=switch, host=host, controller=controller, link=link,
+                  ipBase=opts.ipbase, inNamespace=opts.innamespace,
+                  xterms=opts.xterms, autoSetMacs=opts.mac,
+                  autoStaticArp=opts.arp, autoPinCpus=opts.pin,
+                  waitConnected=opts.wait,
+                  listenPort=opts.listenport )
 
-        if self.options.nat:
-            nat = mn.addNAT()
-            nat.configDefault()
+        if opts.ensure_value( 'nat', False ):
+            with open( '/etc/resolv.conf' ) as f:
+                if 'nameserver 127.' in f.read():
+                    warn( '*** Warning: loopback address in /etc/resolv.conf '
+                          'may break host DNS over NAT\n')
+            mn.addNAT( *opts.nat_args, **opts.nat_kwargs ).configDefault()
 
-        if self.options.pre:
-            CLI( mn, script=self.options.pre )
+        # --custom files can set CLI or change mininet.cli.CLI
+        CLI = mininet.cli.CLI if CLI is None else CLI
 
-        test = self.options.test
-        test = ALTSPELLING.get( test, test )
+        if opts.pre:
+            CLI( mn, script=opts.pre )
 
         mn.start()
 
-        if test == 'none':
-            pass
-        elif test == 'all':
-            mn.waitConnected()
-            mn.start()
-            mn.ping()
-            mn.iperf()
-        elif test == 'cli':
+        if opts.test:
+            runTests( mn, opts.test )
+        else:
             CLI( mn )
-        elif test != 'build':
-            mn.waitConnected()
-            getattr( mn, test )()
 
-        if self.options.post:
-            CLI( mn, script=self.options.post )
+        if opts.post:
+            CLI( mn, script=opts.post )
 
         mn.stop()
 
@@ -334,7 +436,7 @@ if __name__ == "__main__":
     except KeyboardInterrupt:
         info( "\n\nKeyboard Interrupt. Shutting down and cleaning up...\n\n")
         cleanup()
-    except Exception:
+    except Exception:  # pylint: disable=broad-except
         # Print exception
         type_, val_, trace_ = sys.exc_info()
         errorMsg = ( "-"*80 + "\n" +

custom/topo-2sw-2host.py

@@ -13,12 +13,9 @@ from mininet.topo import Topo
 class MyTopo( Topo ):
     "Simple topology example."
 
-    def __init__( self ):
+    def build( self ):
         "Create custom topo."
 
-        # Initialize topology
-        Topo.__init__( self )
-
         # Add hosts and switches
         leftHost = self.addHost( 'h1' )
         rightHost = self.addHost( 'h2' )

examples/README.md

@@ -11,6 +11,31 @@ Mininet's Python API.
 This example uses Mininet's medium-level API to create an sshd
 process running in a namespace. Doesn't use OpenFlow.
 
+#### bind.py:
+
+This example shows how you can create private directories for each
+node in a Mininet topology.
+
+#### cluster.py:
+
+This example contains all of the code for experimental cluster
+edition. Remote classes and MininetCluster can be imported from
+here to create a topology with nodes on remote machines.
+
+#### clusterSanity.py:
+
+This example runs cluster edition locally as a sanity check to test
+basic functionality.
+
+#### clustercli.py:
+
+This example contains a CLI for experimental cluster edition.
+
+#### clusterdemo.py:
+
+This example is a basic demo of cluster edition on 3 servers with
+a tree topology of depth 3 and fanout 3.
+
 #### consoles.py:
 
 This example creates a grid of console windows, one for each node,
@@ -47,6 +72,11 @@ topology object) and adding nodes to it.
 This example shows how to add an interface (for example a real
 hardware interface) to a network after the network is created.
 
+#### intfoptions.py:
+
+This example reconfigures a TCIntf during runtime with different
+traffic control commands to test bandwidth, loss, and delay.
+
 #### limit.py:
 
 This example shows how to use link and CPU limits.
@@ -56,7 +86,7 @@ This example shows how to use link and CPU limits.
 This example shows how to create a custom topology programatically
 by subclassing Topo, and how to run a series of tests on it.
 
-### linuxrouter.py:
+#### linuxrouter.py:
 
 This example shows how to create and configure a router in Mininet
 that uses Linux IP forwarding.
@@ -65,11 +95,16 @@ that uses Linux IP forwarding.
 
 This example demonstrates creating a network via a graphical editor.
 
-#### mobility.py
+#### mobility.py:
 
 This example demonstrates detaching an interface from one switch and
 attaching it another as a basic way to move a host around a network.
 
+#### multiLink.py:
+
+This example demonstrates the creation of multiple links between
+nodes using a custom Topology class.
+
 #### multiping.py:
 
 This example demonstrates one method for
@@ -89,7 +124,12 @@ This example shows how to connect a Mininet network to the Internet
 using NAT. It also answers the eternal question "why can't I ping
 `google.com`?"
 
-#### numberedports.py
+#### natnet.py:
+
+This example demonstrates how to create a network using a NAT node
+to connect hosts to the internet.
+
+#### numberedports.py:
 
 This example verifies the mininet ofport numbers match up to the ovs port numbers.
 It also verifies that the port numbers match up to the interface numbers
@@ -118,7 +158,7 @@ A simple example of configuring network and CPU bandwidth limits.
 
 This example shows how to run an `sshd` process in each host, allowing
 you to log in via `ssh`. This requires connecting the Mininet data network
-to an interface in the root namespace (generaly the control network
+to an interface in the root namespace (generally the control network
 already lives in the root namespace, so it does not need to be explicitly
 connected.)
 

examples/baresshd.py

@@ -1,34 +1,36 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 "This example doesn't use OpenFlow, but attempts to run sshd in a namespace."
 
 import sys
+
 from mininet.node import Host
 from mininet.util import ensureRoot, waitListening
+from mininet.log import info, warn, output
+
 
 ensureRoot()
 timeout = 5
 
-print "*** Creating nodes"
+info( "*** Creating nodes\n" )
 h1 = Host( 'h1' )
 
 root = Host( 'root', inNamespace=False )
 
-print "*** Creating links"
+info( "*** Creating link\n" )
 h1.linkTo( root )
 
-print h1
+info( h1 )
 
-print "*** Configuring nodes"
+info( "*** Configuring nodes\n" )
 h1.setIP( '10.0.0.1', 8 )
 root.setIP( '10.0.0.2', 8 )
 
-print "*** Creating banner file"
-f = open( '/tmp/%s.banner' % h1.name, 'w' )
-f.write( 'Welcome to %s at %s\n' % ( h1.name, h1.IP() ) )
-f.close()
+info( "*** Creating banner file\n" )
+with open( '/tmp/%s.banner' % h1.name, 'w' ) as f:
+    f.write( 'Welcome to %s at %s\n' % ( h1.name, h1.IP() ) )
 
-print "*** Running sshd"
+info( "*** Running sshd\n" )
 cmd = '/usr/sbin/sshd -o UseDNS=no -u0 -o "Banner /tmp/%s.banner"' % h1.name
 # add arguments from the command line
 if len( sys.argv ) > 1:
@@ -37,7 +39,7 @@ h1.cmd( cmd )
 listening = waitListening( server=h1, port=22, timeout=timeout )
 
 if listening:
-    print "*** You may now ssh into", h1.name, "at", h1.IP()
+    output( "*** You may now ssh into", h1.name, "at", h1.IP(), '\n' )
 else:
-    print ( "*** Warning: after %s seconds, %s is not listening on port 22"
-            % ( timeout, h1.name ) )
+    warn( "*** Warning: after %s seconds, %s is not listening on port 22"
+            % ( timeout, h1.name ), '\n' )

examples/bind.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 bind.py: Bind mount example
@@ -22,7 +22,7 @@ to temporary private directories. To do this, simply create a list of
 directories to be made private. A tmpfs will then be mounted on them.
 
 You may use both temporary and persistent directories at the same
-time. In the following privateDirs string, each host will have a 
+time. In the following privateDirs string, each host will have a
 persistent directory in the root filesystem at
 "/tmp/(hostname)/var/run" mounted on "/var/run". Each host will also
 have a temporary private directory mounted on "/var/log".
@@ -34,13 +34,13 @@ and '/var/run'. It also has a temporary private directory mounted
 on '/var/mn'
 """
 
+from functools import partial
+
 from mininet.net import Mininet
-from mininet.node import Host, HostWithPrivateDirs
+from mininet.node import Host
 from mininet.cli import CLI
 from mininet.topo import SingleSwitchTopo
-from mininet.log import setLogLevel, info, debug
-
-from functools import partial
+from mininet.log import setLogLevel, info
 
 
 # Sample usage
@@ -48,25 +48,21 @@ from functools import partial
 def testHostWithPrivateDirs():
     "Test bind mounts"
     topo = SingleSwitchTopo( 10 )
-    privateDirs = [ ( '/var/log', '/tmp/%(name)s/var/log' ), 
-                    ( '/var/run', '/tmp/%(name)s/var/run' ), 
+    privateDirs = [ ( '/var/log', '/tmp/%(name)s/var/log' ),
+                    ( '/var/run', '/tmp/%(name)s/var/run' ),
                       '/var/mn' ]
-    host = partial( HostWithPrivateDirs,
+    host = partial( Host,
                     privateDirs=privateDirs )
-    net = Mininet( topo=topo, host=host )
+    net = Mininet( topo=topo, host=host, waitConnected=True )
     net.start()
-    directories = []
-    for directory in privateDirs:
-        directories.append( directory[ 0 ]
-                            if isinstance( directory, tuple )
-                            else directory )
-    info( 'Private Directories:',  directories, '\n' )
+    directories = [ directory[ 0 ] if isinstance( directory, tuple )
+                    else directory for directory in privateDirs ]
+    info( 'Private Directories:', directories, '\n' )
     CLI( net )
     net.stop()
 
+
 if __name__ == '__main__':
     setLogLevel( 'info' )
     testHostWithPrivateDirs()
     info( 'Done.\n')
-
-

examples/cluster.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 cluster.py: prototyping/experimentation for distributed Mininet,
@@ -74,23 +74,67 @@ Things to do:
 - hifi support (e.g. delay compensation)
 """
 
+from signal import signal, SIGINT, SIG_IGN
+from subprocess import Popen, PIPE, STDOUT
+import os
+from random import randrange
+import sys
+import re
+from itertools import groupby
+from operator import attrgetter
+
 from mininet.node import Node, Host, OVSSwitch, Controller
 from mininet.link import Link, Intf
 from mininet.net import Mininet
 from mininet.topo import LinearTopo
 from mininet.topolib import TreeTopo
-from mininet.util import quietRun, makeIntfPair, errRun, retry
+from mininet.util import quietRun, errRun, decode, StrictVersion
 from mininet.examples.clustercli import CLI
 from mininet.log import setLogLevel, debug, info, error
+from mininet.clean import addCleanupCallback
 
-from signal import signal, SIGINT, SIGHUP, SIG_IGN
-from subprocess import Popen, PIPE, STDOUT
-import os
-from random import randrange
-from sys import exit
-import re
+# pylint: disable=too-many-arguments
 
-from distutils.version import StrictVersion
+
+def findUser():
+    "Try to return logged-in (usually non-root) user"
+    return (
+            # If we're running sudo
+            os.environ.get( 'SUDO_USER', False ) or
+            # Logged-in user (if we have a tty)
+            ( quietRun( 'who am i' ).split() or [ False ] )[ 0 ] or
+            # Give up and return effective user
+            quietRun( 'whoami' ).strip() )
+
+
+class ClusterCleanup( object ):
+    "Cleanup callback"
+
+    inited = False
+    serveruser = {}
+
+    @classmethod
+    def add( cls, server, user='' ):
+        "Add an entry to server: user dict"
+        if not cls.inited:
+            addCleanupCallback( cls.cleanup )
+        if not user:
+            user = findUser()
+        cls.serveruser[ server ] = user
+
+    @classmethod
+    def cleanup( cls ):
+        "Clean up"
+        info( '*** Cleaning up cluster\n' )
+        for server, user in cls.serveruser.items():
+            if server == 'localhost':
+                # Handled by mininet.clean.cleanup()
+                continue
+            else:
+                cmd = [ 'su', user, '-c',
+                        'ssh %s@%s sudo mn -c' % ( user, server ) ]
+                info( cmd, '\n' )
+                info( quietRun( cmd ) )
 
 # BL note: so little code is required for remote nodes,
 # we will probably just want to update the main Node()
@@ -112,68 +156,55 @@ class RemoteMixin( object ):
                 '-o', 'BatchMode=yes',
                 '-o', 'ForwardAgent=yes', '-tt' ]
 
-    def __init__( self, name, server=None, user=None, serverIP=None,
-                  controlPath='/tmp/mn-%r@%h:%p', splitInit=False, **kwargs):
+    def __init__( self, name, server='localhost', user=None, serverIP=None,
+                  controlPath=False, splitInit=False, **kwargs):
         """Instantiate a remote node
            name: name of remote node
            server: remote server (optional)
            user: user on remote server (optional)
-           controlPath: ssh control path template (optional)
+           controlPath: specify shared ssh control path (optional)
            splitInit: split initialization?
            **kwargs: see Node()"""
         # We connect to servers by IP address
-        if server == 'localhost':
-            server = None
-        self.server = server
-        self.serverIP = serverIP if serverIP else self.findServerIP( server )
-        self.user = user if user else self.findUser()
-        if self.user and self.server:
-            self.dest = '%s@%s' % ( self.user, self.serverIP )
-        else:
-            self.dest = None
+        self.server = server if server else 'localhost'
+        self.serverIP = ( serverIP if serverIP
+                          else self.findServerIP( self.server ) )
+        self.user = user if user else findUser()
+        ClusterCleanup.add( server=server, user=user )
+        if controlPath is True:
+            # Set a default control path for shared SSH connections
+            controlPath = '/tmp/mn-%r@%h:%p'
         self.controlPath = controlPath
-        self.sshcmd = []
-        if self.dest:
+        self.splitInit = splitInit
+        if self.user and self.server != 'localhost':
+            self.dest = '%s@%s' % ( self.user, self.serverIP )
             self.sshcmd = [ 'sudo', '-E', '-u', self.user ] + self.sshbase
             if self.controlPath:
                 self.sshcmd += [ '-o', 'ControlPath=' + self.controlPath,
-                                               '-o', 'ControlMaster=auto' ]
-            self.sshcmd = self.sshcmd + [ self.dest ]
-        self.splitInit = splitInit
+                                 '-o', 'ControlMaster=auto',
+                                 '-o', 'ControlPersist=' + '1' ]
+            self.sshcmd += [ self.dest ]
+            self.isRemote = True
+        else:
+            self.dest = None
+            self.sshcmd = []
+            self.isRemote = False
+        # Satisfy pylint
+        self.shell, self.pid = None, None
         super( RemoteMixin, self ).__init__( name, **kwargs )
 
-    @staticmethod
-    def findUser():
-        "Try to return logged-in (usually non-root) user"
-        try:
-            # If we're running sudo
-            return os.environ[ 'SUDO_USER' ]
-        except:
-            try:
-                # Logged-in user (if we have a tty)
-                return quietRun( 'who am i' ).split()[ 0 ]
-            except:
-                # Give up and return effective user
-                return quietRun( 'whoami' )
-
     # Determine IP address of local host
     _ipMatchRegex = re.compile( r'\d+\.\d+\.\d+\.\d+' )
 
     @classmethod
-    def findServerIP( cls, server, intf='eth0' ):
+    def findServerIP( cls, server ):
         "Return our server's IP address"
-        # Check for this server
-        if not server:
-            output = quietRun( 'ifconfig %s' % intf  )
-        # Otherwise, handle remote server
-        else:
-            # First, check for an IP address
-            if server:
-                ipmatch = cls._ipMatchRegex.findall( server )
-                if ipmatch:
-                    return ipmatch[ 0 ]
-            # Otherwise, look up remote server
-            output = quietRun( 'getent ahostsv4 %s' % server )
+        # First, check for an IP address
+        ipmatch = cls._ipMatchRegex.findall( server )
+        if ipmatch:
+            return ipmatch[ 0 ]
+        # Otherwise, look up remote server
+        output = quietRun( 'getent ahostsv4 %s' % server )
         ips = cls._ipMatchRegex.findall( output )
         ip = ips[ 0 ] if ips else None
         return ip
@@ -181,15 +212,16 @@ class RemoteMixin( object ):
     # Command support via shell process in namespace
     def startShell( self, *args, **kwargs ):
         "Start a shell process for running commands"
-        if self.dest:
+        if self.isRemote:
             kwargs.update( mnopts='-c' )
         super( RemoteMixin, self ).startShell( *args, **kwargs )
-        if self.splitInit:
-            self.sendCmd( 'echo $$' )
-        else:
-            self.pid = int( self.cmd( 'echo $$' ) )
+        # Optional split initialization
+        self.sendCmd( 'echo $$' )
+        if not self.splitInit:
+            self.finishInit()
 
     def finishInit( self ):
+        "Wait for split initialization to complete"
         self.pid = int( self.waitOutput() )
 
     def rpopen( self, *cmd, **opts ):
@@ -207,14 +239,14 @@ class RemoteMixin( object ):
            args: string or list of strings
            returns: stdout and stderr"""
         popen = self.rpopen( *cmd, **opts )
-        # print 'RCMD: POPEN:', popen
+        # info( 'RCMD: POPEN:', popen, '\n' )
         # These loops are tricky to get right.
         # Once the process exits, we can read
         # EOF twice if necessary.
         result = ''
         while True:
             poll = popen.poll()
-            result += popen.stdout.read()
+            result += decode( popen.stdout.read() )
             if poll is not None:
                 break
         return result
@@ -229,9 +261,9 @@ class RemoteMixin( object ):
             cmd: remote command to run (list)
             **params: parameters to Popen()
             returns: Popen() object"""
-        if type( cmd ) is str:
+        if isinstance( cmd, str):
             cmd = cmd.split()
-        if self.dest:
+        if self.isRemote:
             if sudo:
                 cmd = [ 'sudo', '-E' ] + cmd
             if tt:
@@ -246,7 +278,7 @@ class RemoteMixin( object ):
                 # Drop privileges
                 cmd = [ 'sudo', '-E', '-u', self.user ] + cmd
         params.update( preexec_fn=self._ignoreSignal )
-        debug( '_popen', ' '.join(cmd), params )
+        debug( '_popen', cmd, '\n' )
         popen = super( RemoteMixin, self )._popen( cmd, **params )
         return popen
 
@@ -256,8 +288,9 @@ class RemoteMixin( object ):
 
     def addIntf( self, *args, **kwargs ):
         "Override: use RemoteLink.moveIntf"
-        return super( RemoteMixin, self).addIntf( *args,
-                        moveIntfFn=RemoteLink.moveIntf, **kwargs )
+        # kwargs.update( moveIntfFn=RemoteLink.moveIntf )
+        # pylint: disable=useless-super-delegation
+        return super( RemoteMixin, self).addIntf( *args, **kwargs )
 
 
 class RemoteNode( RemoteMixin, Node ):
@@ -272,20 +305,52 @@ class RemoteHost( RemoteNode ):
 
 class RemoteOVSSwitch( RemoteMixin, OVSSwitch ):
     "Remote instance of Open vSwitch"
+
     OVSVersions = {}
-    def isOldOVS( self ):
+
+    def __init__( self, *args, **kwargs ):
+        # No batch startup yet
+        kwargs.update( batch=True )
+        super( RemoteOVSSwitch, self ).__init__( *args, **kwargs )
+
+    def isOldOVS( self ):  # pylint: disable=arguments-differ
         "Is remote switch using an old OVS version?"
         cls = type( self )
         if self.server not in cls.OVSVersions:
+            # pylint: disable=not-callable
             vers = self.cmd( 'ovs-vsctl --version' )
-            cls.OVSVersions[ self.server ] = re.findall( '\d+\.\d+', vers )[ 0 ]
+            # pylint: enable=not-callable
+            cls.OVSVersions[ self.server ] = re.findall(
+                r'\d+\.\d+', vers )[ 0 ]
         return ( StrictVersion( cls.OVSVersions[ self.server ] ) <
-                StrictVersion( '1.10' ) )
+                 StrictVersion( '1.10' ) )
 
+    @classmethod
+    # pylint: disable=arguments-differ
+    def batchStartup( cls, switches, **_kwargs ):
+        "Start up switches in per-server batches"
+        key = attrgetter( 'server' )
+        for server, switchGroup in groupby( sorted( switches, key=key ), key ):
+            info( '(%s)' % server )
+            group = tuple( switchGroup )
+            switch = group[ 0 ]
+            OVSSwitch.batchStartup( group, run=switch.cmd )
+        return switches
+
+    @classmethod
+    # pylint: disable=arguments-differ
+    def batchShutdown( cls, switches, **_kwargs ):
+        "Stop switches in per-server batches"
+        key = attrgetter( 'server' )
+        for server, switchGroup in groupby( sorted( switches, key=key ), key ):
+            info( '(%s)' % server )
+            group = tuple( switchGroup )
+            switch = group[ 0 ]
+            OVSSwitch.batchShutdown( group, run=switch.rcmd )
+        return switches
 
 
 class RemoteLink( Link ):
-
     "A RemoteLink is a link between nodes which may be on different servers"
 
     def __init__( self, node1, node2, **kwargs ):
@@ -297,64 +362,74 @@ class RemoteLink( Link ):
         self.tunnel = None
         kwargs.setdefault( 'params1', {} )
         kwargs.setdefault( 'params2', {} )
+        self.cmd = None  # satisfy pylint
         Link.__init__( self, node1, node2, **kwargs )
 
     def stop( self ):
         "Stop this link"
         if self.tunnel:
             self.tunnel.terminate()
+            self.intf1.delete()
+            self.intf2.delete()
+        else:
+            Link.stop( self )
         self.tunnel = None
 
-    def makeIntfPair( self, intfname1, intfname2, addr1=None, addr2=None ):
+    def makeIntfPair( self,  # pylint: disable=arguments-renamed
+                      intfname1, intfname2, addr1=None, addr2=None,
+                      node1=None, node2=None, deleteIntfs=True ):
         """Create pair of interfaces
             intfname1: name of interface 1
             intfname2: name of interface 2
             (override this method [and possibly delete()]
             to change link type)"""
-        node1, node2 = self.node1, self.node2
-        server1 = getattr( node1, 'server', None )
-        server2 = getattr( node2, 'server', None )
-        if not server1 and not server2:
-            # Local link
-            return makeIntfPair( intfname1, intfname2, addr1, addr2 )
-        elif server1 == server2:
-            # Remote link on same remote server
-            return makeIntfPair( intfname1, intfname2, addr1, addr2,
-                                 run=node1.rcmd )
+        node1 = self.node1 if node1 is None else node1
+        node2 = self.node2 if node2 is None else node2
+        server1 = getattr( node1, 'server', 'localhost' )
+        server2 = getattr( node2, 'server', 'localhost' )
+        if server1 == server2:
+            # Link within same server
+            return Link.makeIntfPair( intfname1, intfname2, addr1, addr2,
+                                      node1, node2, deleteIntfs=deleteIntfs )
         # Otherwise, make a tunnel
-        self.tunnel = self.makeTunnel( node1, node2, intfname1, intfname2, addr1, addr2 )
+        self.tunnel = self.makeTunnel( node1, node2, intfname1, intfname2,
+                                       addr1, addr2 )
         return self.tunnel
 
     @staticmethod
-    def moveIntf( intf, node, printError=True ):
+    def moveIntf( intf, node ):
         """Move remote interface from root ns to node
             intf: string, interface
             dstNode: destination Node
-            srcNode: source Node or None (default) for root ns
-            printError: if true, print error"""
+            srcNode: source Node or None (default) for root ns"""
         intf = str( intf )
         cmd = 'ip link set %s netns %s' % ( intf, node.pid )
-        node.rcmd( cmd )
-        links = node.cmd( 'ip link show' )
-        if not ( ' %s:' % intf ) in links:
-            if printError:
-                error( '*** Error: RemoteLink.moveIntf: ' + intf +
-                      ' not successfully moved to ' + node.name + '\n' )
-            return False
+        result = node.rcmd( cmd )
+        if result:
+            raise Exception('error executing command %s' % cmd)
         return True
-    
+
     def makeTunnel( self, node1, node2, intfname1, intfname2,
                     addr1=None, addr2=None ):
         "Make a tunnel across switches on different servers"
+        # We should never try to create a tunnel to ourselves!
+        assert node1.server != node2.server
+        # And we can't ssh into this server remotely as 'localhost',
+        # so try again swappping node1 and node2
+        if node2.server == 'localhost':
+            return self.makeTunnel( node1=node2, node2=node1,
+                                    intfname1=intfname2, intfname2=intfname1,
+                                    addr1=addr2, addr2=addr1 )
+        debug( '\n*** Make SSH tunnel ' + node1.server + ':' + intfname1 +
+               ' == ' + node2.server + ':' + intfname2 )
         # 1. Create tap interfaces
         for node in node1, node2:
             # For now we are hard-wiring tap9, which we will rename
-            node.rcmd( 'ip link delete tap9', stderr=PIPE )
             cmd = 'ip tuntap add dev tap9 mode tap user ' + node.user
-            node.rcmd( cmd )
-            links = node.rcmd( 'ip link show' )
-            # print 'after add, links =', links
-            assert 'tap9' in links
+            result = node.rcmd( cmd )
+            if result:
+                raise Exception( 'error creating tap9 on %s: %s' %
+                                 ( node, result ) )
         # 2. Create ssh tunnel between tap interfaces
         # -n: close stdin
         dest = '%s@%s' % ( node2.user, node2.serverIP )
@@ -365,31 +440,30 @@ class RemoteLink( Link ):
         # When we receive the character '@', it means that our
         # tunnel should be set up
         debug( 'Waiting for tunnel to come up...\n' )
-        ch = tunnel.stdout.read( 1 )
+        ch = decode( tunnel.stdout.read( 1 ) )
         if ch != '@':
-            error( 'makeTunnel:\n',
-                   'Tunnel setup failed for',
-                   '%s:%s' % ( node1, node1.dest ), 'to', 
-                   '%s:%s\n' % ( node2, node2.dest ),
-                  'command was:', cmd, '\n' )
-            tunnel.terminate()
-            tunnel.wait()
-            error( ch + tunnel.stdout.read() )
-            error( tunnel.stderr.read() )
-            exit( 1 )
+            ch += decode( tunnel.stdout.read() )
+            cmd = ' '.join( cmd )
+            raise Exception( 'makeTunnel:\n'
+                             'Tunnel setup failed for '
+                             '%s:%s' % ( node1, node1.dest ) + ' to '
+                             '%s:%s\n' % ( node2, node2.dest ) +
+                             'command was: %s' % cmd + '\n' +
+                             'result was: ' + ch )
         # 3. Move interfaces if necessary
         for node in node1, node2:
-            if node.inNamespace:
-                retry( 3, .01, RemoteLink.moveIntf, 'tap9', node )
+            if not self.moveIntf( 'tap9', node ):
+                raise Exception( 'interface move failed on node %s' % node )
         # 4. Rename tap interfaces to desired names
         for node, intf, addr in ( ( node1, intfname1, addr1 ),
-                            ( node2, intfname2, addr2 ) ):
+                                  ( node2, intfname2, addr2 ) ):
             if not addr:
-                node.cmd( 'ip link set tap9 name', intf )
+                result = node.cmd( 'ip link set tap9 name', intf )
             else:
-                node.cmd( 'ip link set tap9 name', intf, 'address', addr )
-        for node, intf in ( ( node1, intfname1 ), ( node2, intfname2 ) ):
-            assert intf in node.cmd( 'ip link show' )
+                result = node.cmd( 'ip link set tap9 name', intf,
+                                   'address', addr )
+            if result:
+                raise Exception( 'error renaming %s: %s' % ( intf, result ) )
         return tunnel
 
     def status( self ):
@@ -406,13 +480,100 @@ class RemoteLink( Link ):
         return result
 
 
+class RemoteSSHLink( RemoteLink ):
+    "Remote link using SSH tunnels"
+    def __init__(self, node1, node2, **kwargs):
+        RemoteLink.__init__( self, node1, node2, **kwargs )
+
+
+class RemoteGRELink( RemoteLink ):
+    "Remote link using GRE tunnels"
+
+    GRE_KEY = 0
+
+    def __init__(self, node1, node2, **kwargs):
+        RemoteLink.__init__( self, node1, node2, **kwargs )
+
+    def stop( self ):
+        "Stop this link"
+        if self.tunnel:
+            self.intf1.delete()
+            self.intf2.delete()
+        else:
+            Link.stop( self )
+        self.tunnel = None
+
+    def makeIntfPair( self, intfname1, intfname2, addr1=None, addr2=None,
+                      node1=None, node2=None, deleteIntfs=True   ):
+        """Create pair of interfaces
+            intfname1: name of interface 1
+            intfname2: name of interface 2
+            (override this method [and possibly delete()]
+            to change link type)"""
+        node1 = self.node1 if node1 is None else node1
+        node2 = self.node2 if node2 is None else node2
+        server1 = getattr( node1, 'server', 'localhost' )
+        server2 = getattr( node2, 'server', 'localhost' )
+        if server1 == server2:
+            # Link within same server
+            Link.makeIntfPair( intfname1, intfname2, addr1, addr2,
+                               node1, node2, deleteIntfs=deleteIntfs )
+            # Need to reduce the MTU of all emulated hosts to 1450 for GRE
+            # tunneling, otherwise packets larger than 1400 bytes cannot be
+            # successfully transmitted through the tunnel.
+            node1.cmd('ip link set dev %s mtu 1450' % intfname1)
+            node2.cmd('ip link set dev %s mtu 1450' % intfname2)
+        else:
+            # Otherwise, make a tunnel
+            self.makeTunnel( node1, node2, intfname1, intfname2, addr1, addr2 )
+            self.tunnel = 1
+
+    def makeTunnel(self, node1, node2, intfname1, intfname2,
+                       addr1=None, addr2=None):
+        "Make a tunnel across switches on different servers"
+        # We should never try to create a tunnel to ourselves!
+        assert node1.server != node2.server
+        if node2.server == 'localhost':
+            return self.makeTunnel( node1=node2, node2=node1,
+                                    intfname1=intfname2, intfname2=intfname1,
+                                    addr1=addr2, addr2=addr1 )
+        IP1, IP2 = node1.serverIP, node2.serverIP
+        # GRE tunnel needs to be set up with the IP of the local interface
+        # that connects the remote node, NOT '127.0.0.1' of localhost
+        if node1.server == 'localhost':
+            output = quietRun('ip route get %s' % node2.serverIP)
+            IP1 = output.split(' src ')[1].split()[0]
+        debug( '\n*** Make GRE tunnel ' + node1.server + ':' + intfname1 +
+               ' == ' + node2.server + ':' + intfname2 )
+        tun1 = 'local ' + IP1 + ' remote ' + IP2
+        tun2 = 'local ' + IP2 + ' remote ' + IP1
+        self.__class__.GRE_KEY += 1
+        for (node, intfname, addr, tun) in [(node1, intfname1, addr1, tun1),
+                                            (node2, intfname2, addr2, tun2)]:
+            node.rcmd('ip link delete ' + intfname)
+            result = node.rcmd('ip link add name ' + intfname + ' type gretap '
+                               + tun + ' ttl 64 key '
+                               + str( self.__class__.GRE_KEY) )
+            if result:
+                raise Exception('error creating gretap on %s: %s'
+                                % (node, result))
+            if addr:
+                node.rcmd('ip link set %s address %s' % (intfname, addr))
+
+            node.rcmd('ip link set dev %s up' % intfname)
+            node.rcmd('ip link set dev %s mtu 1450' % intfname)
+            if not self.moveIntf(intfname, node):
+                raise Exception('interface move failed on node %s' % node)
+        return None  # May want to return something useful here
+
+
 # Some simple placement algorithms for MininetCluster
 
 class Placer( object ):
     "Node placement algorithm for MininetCluster"
-    
+
     def __init__( self, servers=None, nodes=None, hosts=None,
-                 switches=None, controllers=None, links=None ):
+                  switches=None, controllers=None, links=None ):
         """Initialize placement object
            servers: list of servers
            nodes: list of all nodes
@@ -431,15 +592,17 @@ class Placer( object ):
 
     def place( self, node ):
         "Return server for a given node"
+        assert self, node  # satisfy pylint
         # Default placement: run locally
-        return None
+        return 'localhost'
 
 
 class RandomPlacer( Placer ):
     "Random placement"
-    def place( self, nodename ):
+    def place( self, node ):
         """Random placement function
-            nodename: node name"""
+            node: node"""
+        assert node  # please pylint
         # This may be slow with lots of servers
         return self.servers[ randrange( 0, len( self.servers ) ) ]
 
@@ -448,14 +611,15 @@ class RoundRobinPlacer( Placer ):
     """Round-robin placement
        Note this will usually result in cross-server links between
        hosts and switches"""
-    
+
     def __init__( self, *args, **kwargs ):
         Placer.__init__( self, *args, **kwargs )
         self.next = 0
 
-    def place( self, nodename ):
+    def place( self, node ):
         """Round-robin placement function
-            nodename: node name"""
+            node: node"""
+        assert node  # please pylint
         # This may be slow with lots of servers
         server = self.servers[ self.next ]
         self.next = ( self.next + 1 ) % len( self.servers )
@@ -474,7 +638,7 @@ class SwitchBinPlacer( Placer ):
         self.sset = frozenset( self.switches )
         self.cset = frozenset( self.controllers )
         # Server and switch placement indices
-        self.placement =  self.calculatePlacement()
+        self.placement = self.calculatePlacement()
 
     @staticmethod
     def bin( nodes, servers ):
@@ -493,7 +657,7 @@ class SwitchBinPlacer( Placer ):
         tickets = sum( [ binsizes[ server ] * [ server ]
                          for server in servers ], [] )
         # And assign one ticket to each node
-        return { node: ticket for node, ticket in zip( nodes, tickets ) }
+        return dict( zip( nodes, tickets ) )
 
     def calculatePlacement( self ):
         "Pre-calculate node placement"
@@ -541,7 +705,7 @@ class HostSwitchBinPlacer( Placer ):
         scount = len( self.servers )
         self.hbin = max( int( len( self.hosts ) / scount ), 1 )
         self.sbin = max( int( len( self.switches ) / scount ), 1 )
-        self.cbin = max( int( len( self.controllers ) / scount ) , 1 )
+        self.cbin = max( int( len( self.controllers ) / scount ), 1 )
         info( 'scount:', scount )
         info( 'bins:', self.hbin, self.sbin, self.cbin, '\n' )
         self.servdict = dict( enumerate( self.servers ) )
@@ -549,27 +713,26 @@ class HostSwitchBinPlacer( Placer ):
         self.sset = frozenset( self.switches )
         self.cset = frozenset( self.controllers )
         self.hind, self.sind, self.cind = 0, 0, 0
-    
-    def place( self, nodename ):
+
+    def place( self, node ):
         """Simple placement algorithm:
             place nodes into evenly sized bins"""
         # Place nodes into bins
-        if nodename in self.hset:
+        if node in self.hset:
             server = self.servdict[ self.hind / self.hbin ]
             self.hind += 1
-        elif nodename in self.sset:
+        elif node in self.sset:
             server = self.servdict[ self.sind / self.sbin ]
             self.sind += 1
-        elif nodename in self.cset:
+        elif node in self.cset:
             server = self.servdict[ self.cind / self.cbin ]
             self.cind += 1
         else:
-            info( 'warning: unknown node', nodename )
+            info( 'warning: unknown node', node )
             server = self.servdict[ 0 ]
         return server
 
 
-
 # The MininetCluster class is not strictly necessary.
 # However, it has several purposes:
 # 1. To set up ssh connection sharing/multiplexing
@@ -596,14 +759,14 @@ class MininetCluster( Mininet ):
                    'link': RemoteLink,
                    'precheck': True }
         params.update( kwargs )
-        servers = params.pop( 'servers', [ None ] )
-        servers = [ s if s != 'localhost' else None for s in servers ]
+        servers = params.pop( 'servers', [ 'localhost' ] )
+        servers = [ s if s else 'localhost' for s in servers ]
         self.servers = servers
         self.serverIP = params.pop( 'serverIP', {} )
         if not self.serverIP:
             self.serverIP = { server: RemoteMixin.findServerIP( server )
                               for server in self.servers }
-        self.user = params.pop( 'user', RemoteMixin.findUser() )
+        self.user = params.pop( 'user', findUser() )
         if params.pop( 'precheck' ):
             self.precheck()
         self.connections = {}
@@ -611,12 +774,16 @@ class MininetCluster( Mininet ):
         # Make sure control directory exists
         self.cdir = os.environ[ 'HOME' ] + '/.ssh/mn'
         errRun( [ 'mkdir', '-p', self.cdir ] )
+        # pylint: disable=unexpected-keyword-arg
         Mininet.__init__( self, *args, **params )
 
     def popen( self, cmd ):
         "Popen() for server connections"
+        assert self  # please pylint
         old = signal( SIGINT, SIG_IGN )
+        # pylint: disable=consider-using-with
         conn = Popen( cmd, stdin=PIPE, stdout=PIPE, close_fds=True )
+        # pylint: enable=consider-using-with
         signal( SIGINT, old )
         return conn
 
@@ -632,13 +799,13 @@ class MininetCluster( Mininet ):
         for server in self.servers:
             ip = self.serverIP[ server ]
             if not server or server == 'localhost':
-                 continue
+                continue
             info( server, '' )
             dest = '%s@%s' % ( self.user, ip )
             cmd = [ 'sudo', '-E', '-u', self.user ]
             cmd += self.sshcmd + [ '-n', dest, 'sudo true' ]
             debug( ' '.join( cmd ), '\n' )
-            out, err, code = errRun( cmd )
+            _out, _err, code = errRun( cmd )
             if code != 0:
                 error( '\nstartConnection: server connection check failed '
                        'to %s using command:\n%s\n'
@@ -646,18 +813,19 @@ class MininetCluster( Mininet ):
             result |= code
         if result:
             error( '*** Server precheck failed.\n'
-                   '*** Make sure that the above ssh command works correctly.\n'
+                   '*** Make sure that the above ssh command works'
+                   ' correctly.\n'
                    '*** You may also need to run mn -c on all nodes, and/or\n'
                    '*** use sudo -E.\n' )
-            exit( 1 )
+            sys.exit( 1 )
         info( '\n' )
 
     def modifiedaddHost( self, *args, **kwargs ):
         "Slightly modify addHost"
+        assert self  # please pylint
         kwargs[ 'splitInit' ] = True
         return Mininet.addHost( *args, **kwargs )
 
-
     def placeNodes( self ):
         """Place nodes on servers (if they don't have a server), and
            start shell processes"""
@@ -671,7 +839,10 @@ class MininetCluster( Mininet ):
                                  switches=self.topo.switches(),
                                  links=self.topo.links() )
         for node in nodes:
-            config = self.topo.node_info[ node ]
+            config = self.topo.nodeInfo( node )
+            # keep local server name consistent accross nodes
+            if 'server' in config.keys() and config[ 'server' ] is None:
+                config[ 'server' ] = 'localhost'
             server = config.setdefault( 'server', placer.place( node ) )
             if server:
                 config.setdefault( 'serverIP', self.serverIP[ server ] )
@@ -682,16 +853,43 @@ class MininetCluster( Mininet ):
             if cfile:
                 config.setdefault( 'controlPath', cfile )
 
+    @staticmethod
+    def isLoopback( ipaddr ):
+        "Is ipaddr an IPv4 loopback address?"
+        return ipaddr.startswith( '127.' )
+
+    # pylint: disable=arguments-differ,signature-differs
     def addController( self, *args, **kwargs ):
         "Patch to update IP address to global IP address"
         controller = Mininet.addController( self, *args, **kwargs )
-        # Update IP address for controller that may not be local
-        if ( isinstance( controller, Controller)
-             and controller.IP() == '127.0.0.1'
-             and ' eth0:' in controller.cmd( 'ip link show' ) ):
-             Intf( 'eth0', node=controller ).updateIP()
+        controllerIP = controller.IP()
+        if ( not isinstance( controller, Controller ) or
+             not self.isLoopback( controller.IP() ) ):
+            return controller
+        # Find route to a different server IP address
+        serverIPs = [ ip for ip in self.serverIP.values()
+                      if ip != controllerIP ]
+        if not serverIPs:
+            return None  # no remote servers - loopback is fine
+        for remoteIP in serverIPs:
+            # Route should contain 'dev <intfname>'
+            route = controller.cmd( 'ip route get', remoteIP,
+                                    r'| egrep -o "dev\s[^[:space:]]+"' )
+            if not route:
+                raise Exception('addController: no route from', controller,
+                                'to', remoteIP )
+            intf = route.split()[ 1 ].strip()
+            if intf != 'lo':
+                break
+        if intf == 'lo':
+            raise Exception( 'addController: could not find external '
+                             'interface/IP for %s' % controller )
+        debug( 'adding', intf, 'to', controller )
+        Intf( intf, node=controller ).updateIP()
+        debug( controller, 'IP address updated to', controller.IP() )
         return controller
 
+    # pylint: disable=arguments-differ,signature-differs
     def buildFromTopo( self, *args, **kwargs ):
         "Start network"
         info( '*** Placing nodes\n' )
@@ -700,11 +898,14 @@ class MininetCluster( Mininet ):
         Mininet.buildFromTopo( self, *args, **kwargs )
 
 
-def testNsTunnels():
+# Default remote server for tests
+remoteServer = 'ubuntu2'
+
+def testNsTunnels( remote=remoteServer, link=RemoteGRELink ):
     "Test tunnels between nodes in namespaces"
-    net = Mininet( host=RemoteHost, link=RemoteLink )
-    h1 = net.addHost( 'h1' )
-    h2 = net.addHost( 'h2', server='ubuntu2' )
+    net = Mininet( host=RemoteHost, link=link, waitConnected=True )
+    h1 = net.addHost( 'h1')
+    h2 = net.addHost( 'h2', server=remote )
     net.addLink( h1, h2 )
     net.start()
     net.pingAll()
@@ -715,30 +916,31 @@ def testNsTunnels():
 # This shows how node options may be used to manage
 # cluster placement using the net.add*() API
 
-def testRemoteNet( remote='ubuntu2' ):
+def testRemoteNet( remote=remoteServer, link=RemoteGRELink ):
     "Test remote Node classes"
-    print '*** Remote Node Test'
+    info( '*** Remote Node Test\n' )
     net = Mininet( host=RemoteHost, switch=RemoteOVSSwitch,
-                   link=RemoteLink )
+                   link=link, controller=ClusterController,
+                   waitConnected=True )
     c0 = net.addController( 'c0' )
     # Make sure controller knows its non-loopback address
-    Intf( 'eth0', node=c0 ).updateIP()
-    print "*** Creating local h1"
+    info( "*** Creating local h1\n" )
     h1 = net.addHost( 'h1' )
-    print "*** Creating remote h2"
+    info( "*** Creating remote h2\n" )
     h2 = net.addHost( 'h2', server=remote )
-    print "*** Creating local s1"
+    info( "*** Creating local s1\n" )
     s1 = net.addSwitch( 's1' )
-    print "*** Creating remote s2"
+    info( "*** Creating remote s2\n" )
     s2 = net.addSwitch( 's2', server=remote )
-    print "*** Adding links"
+    info( "*** Adding links\n" )
     net.addLink( h1, s1 )
     net.addLink( s1, s2 )
     net.addLink( h2, s2 )
     net.start()
-    print 'Mininet is running on', quietRun( 'hostname' ).strip()
+    info( 'Mininet is running on', quietRun( 'hostname' ).strip(), '\n' )
     for node in c0, h1, h2, s1, s2:
-        print 'Node', node, 'is running on', node.cmd( 'hostname' ).strip()
+        info( 'Node', node, 'is running on',
+              node.cmd( 'hostname' ).strip(), '\n' )
     net.pingAll()
     CLI( net )
     net.stop()
@@ -753,7 +955,7 @@ def testRemoteNet( remote='ubuntu2' ):
 
 remoteHosts = [ 'h2' ]
 remoteSwitches = [ 's2' ]
-remoteServer = 'ubuntu2'
+
 
 def HostPlacer( name, *args, **params ):
     "Custom Host() constructor which places hosts on servers"
@@ -770,17 +972,28 @@ def SwitchPlacer( name, *args, **params ):
         return RemoteOVSSwitch( name, *args, **params )
 
 def ClusterController( *args, **kwargs):
-    "Custom Controller() constructor which updates its eth0 IP address"
+    "Custom Controller() constructor which updates its intf IP address"
+    intf = kwargs.pop( 'intf', '' )
     controller = Controller( *args, **kwargs )
     # Find out its IP address so that cluster switches can connect
-    Intf( 'eth0', node=controller ).updateIP()
+    if not intf:
+        output = controller.cmd(
+            r"ip a | egrep -o '\w+:\s\w+'" ).split( '\n' )
+        for line in output:
+            intf = line.split()[ -1 ]
+            if intf != 'lo':
+                break
+        if intf == 'lo':
+            raise Exception( 'Could not find non-loopback interface'
+                             'for %s' % controller )
+    Intf( intf, node=controller ).updateIP()
     return controller
 
-def testRemoteTopo():
+def testRemoteTopo( link=RemoteGRELink ):
     "Test remote Node classes using Mininet()/Topo() API"
     topo = LinearTopo( 2 )
     net = Mininet( topo=topo, host=HostPlacer, switch=SwitchPlacer,
-                  link=RemoteLink, controller=ClusterController )
+                   link=link, controller=ClusterController )
     net.start()
     net.pingAll()
     net.stop()
@@ -790,18 +1003,17 @@ def testRemoteTopo():
 # do random switch placement rather than completely random
 # host placement.
 
-def testRemoteSwitches():
+def testRemoteSwitches( remote=remoteServer, link=RemoteGRELink ):
     "Test with local hosts and remote switches"
-    servers = [ 'localhost', 'ubuntu2']
+    servers = [ 'localhost', remote]
     topo = TreeTopo( depth=4, fanout=2 )
-    net = MininetCluster( topo=topo, servers=servers,
+    net = MininetCluster( topo=topo, servers=servers, link=link,
                           placement=RoundRobinPlacer )
     net.start()
     net.pingAll()
     net.stop()
 
 
-#
 # For testing and demo purposes it would be nice to draw the
 # network graph and color it based on server.
 
@@ -809,31 +1021,35 @@ def testRemoteSwitches():
 # functions, for maximum ease of use. MininetCluster() also
 # pre-flights and multiplexes server connections.
 
-def testMininetCluster():
+def testMininetCluster( remote=remoteServer, link=RemoteGRELink ):
     "Test MininetCluster()"
-    servers = [ 'localhost', 'ubuntu2' ]
+    servers = [ 'localhost', remote ]
     topo = TreeTopo( depth=3, fanout=3 )
-    net = MininetCluster( topo=topo, servers=servers,
+    net = MininetCluster( topo=topo, servers=servers, link=link,
                           placement=SwitchBinPlacer )
     net.start()
     net.pingAll()
     net.stop()
 
-def signalTest():
+def signalTest( remote=remoteServer):
     "Make sure hosts are robust to signals"
-    h = RemoteHost( 'h0', server='ubuntu1' )
+    h = RemoteHost( 'h0', server=remote )
     h.shell.send_signal( SIGINT )
     h.shell.poll()
     if h.shell.returncode is None:
-        print 'OK: ', h, 'has not exited'
+        info( 'signalTest: SUCCESS: ', h, 'has not exited after SIGINT', '\n' )
     else:
-        print 'FAILURE:', h, 'exited with code', h.shell.returncode
+        info( 'signalTest: FAILURE:', h, 'exited with code',
+              h.shell.returncode, '\n' )
     h.stop()
 
+
 if __name__ == '__main__':
     setLogLevel( 'info' )
-    # testRemoteTopo()
-    # testRemoteNet()
-    # testMininetCluster()
-    # testRemoteSwitches()
-    signalTest()
+    remoteLink = RemoteSSHLink
+    testRemoteTopo(link=remoteLink)
+    testNsTunnels( remote=remoteServer, link=remoteLink )
+    testRemoteNet( remote=remoteServer, link=remoteLink)
+    testMininetCluster( remote=remoteServer, link=remoteLink)
+    testRemoteSwitches( remote=remoteServer, link=remoteLink)
+    signalTest( remote=remoteServer )

examples/clusterSanity.py

@@ -5,18 +5,19 @@ A sanity check for cluster edition
 '''
 
 from mininet.examples.cluster import MininetCluster
-from mininet.log import info, setLogLevel
-from mininet.examples.clustercli import DemoCLI as CLI
+from mininet.log import setLogLevel
+from mininet.examples.clustercli import ClusterCLI as CLI
 from mininet.topo import SingleSwitchTopo
 
 def clusterSanity():
     "Sanity check for cluster mode"
     topo = SingleSwitchTopo()
-    net = MininetCluster( topo=topo ) 
+    net = MininetCluster( topo=topo )
     net.start()
     CLI( net )
     net.stop()
 
-if __name__  == '__main__':
+
+if __name__ == '__main__':
     setLogLevel( 'info' )
     clusterSanity()

examples/clustercli.py

@@ -1,46 +1,58 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 "CLI for Mininet Cluster Edition prototype demo"
 
 from mininet.cli import CLI
 from mininet.log import output, error
 
+# pylint: disable=global-statement
 nx, graphviz_layout, plt = None, None, None  # Will be imported on demand
 
 
-class DemoCLI( CLI ):
+class ClusterCLI( CLI ):
     "CLI with additional commands for Cluster Edition demo"
 
     @staticmethod
     def colorsFor( seq ):
         "Return a list of background colors for a sequence"
         colors = [ 'red', 'lightgreen', 'cyan', 'yellow', 'orange',
-                  'magenta', 'pink', 'grey', 'brown',
-                  'white' ]
+                   'magenta', 'pink', 'grey', 'brown',
+                   'white' ]
         slen, clen = len( seq ), len( colors )
         reps = max( 1, slen / clen )
         colors = colors * reps
         colors = colors[ 0 : slen ]
         return colors
-    
-    def do_plot( self, line ):
+
+    def do_plot( self, _line ):
         "Plot topology colored by node placement"
         # Import networkx if needed
-        global nx, plt
+        global nx, plt, graphviz_layout
         if not nx:
             try:
-                import networkx as nx
-                import matplotlib.pyplot as plt
+                # pylint: disable=import-error,no-member
+                # pylint: disable=import-outside-toplevel
+                import networkx
+                nx = networkx  # satisfy pylint
+                from matplotlib import pyplot
+                plt = pyplot   # satisfy pylint
                 import pygraphviz
-            except:
+                assert pygraphviz  # silence pyflakes
+                # Networkx moved this around
+                if hasattr( nx, 'graphviz_layout' ):
+                    graphviz_layout = nx.graphviz_layout
+                else:
+                    graphviz_layout = nx.drawing.nx_agraph.graphviz_layout
+                # pylint: enable=import-error,no-member
+            except ImportError:
                 error( 'plot requires networkx, matplotlib and pygraphviz - '
                        'please install them and try again\n' )
                 return
         # Make a networkx Graph
         g = nx.Graph()
         mn = self.mn
-        servers, hosts, switches = mn.servers, mn.hosts, mn.switches
-        hlen, slen = len( hosts ), len( switches )
+        servers = getattr( mn, 'servers', [ 'localhost' ] )
+        hosts, switches = mn.hosts, mn.switches
         nodes = hosts + switches
         g.add_nodes_from( nodes )
         links = [ ( link.intf1.node, link.intf2.node )
@@ -50,13 +62,16 @@ class DemoCLI( CLI ):
         # shapes = hlen * [ 's' ] + slen * [ 'o' ]
         color = dict( zip( servers, self.colorsFor( servers ) ) )
         # Plot it!
-        pos = nx.graphviz_layout( g )
+        pos = graphviz_layout( g )
         opts = { 'ax': None, 'font_weight': 'bold',
-		 'width': 2, 'edge_color': 'darkblue' }
-        hcolors = [ color[ h.server ] for h in hosts ]
-        scolors = [ color[ s.server ] for s in switches ]
-        nx.draw_networkx( g, pos=pos, nodelist=hosts, node_size=800, label='host',
-                          node_color=hcolors, node_shape='s', **opts )
+                 'width': 2, 'edge_color': 'darkblue' }
+        hcolors = [ color[ getattr( h, 'server', 'localhost' ) ]
+                    for h in hosts ]
+        scolors = [ color[ getattr( s, 'server', 'localhost' ) ]
+                    for s in switches ]
+        nx.draw_networkx( g, pos=pos, nodelist=hosts, node_size=800,
+                          label='host', node_color=hcolors, node_shape='s',
+                          **opts )
         nx.draw_networkx( g, pos=pos, nodelist=switches, node_size=1000,
                           node_color=scolors, node_shape='o', **opts )
         # Get rid of axes, add title, and show
@@ -68,7 +83,7 @@ class DemoCLI( CLI ):
         plt.title( 'Node Placement', fontweight='bold' )
         plt.show()
 
-    def do_status( self, line ):
+    def do_status( self, _line ):
         "Report on node shell status"
         nodes = self.mn.hosts + self.mn.switches
         for node in nodes:
@@ -82,8 +97,7 @@ class DemoCLI( CLI ):
         else:
             output( 'All nodes are still running.\n' )
 
-
-    def do_placement( self, line ):
+    def do_placement( self, _line ):
         "Describe node placement"
         mn = self.mn
         nodes = mn.hosts + mn.switches + mn.controllers

examples/clusterdemo.py

@@ -1,23 +1,25 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 "clusterdemo.py: demo of Mininet Cluster Edition prototype"
 
-from mininet.examples.cluster import MininetCluster, SwitchBinPlacer
+from mininet.examples.cluster import ( MininetCluster, SwitchBinPlacer,
+                                       RemoteLink )
+# ^ Could also use: RemoteSSHLink, RemoteGRELink
 from mininet.topolib import TreeTopo
 from mininet.log import setLogLevel
-from mininet.examples.clustercli import DemoCLI as CLI
+from mininet.examples.clustercli import ClusterCLI as CLI
 
 def demo():
     "Simple Demo of Cluster Mode"
     servers = [ 'localhost', 'ubuntu2', 'ubuntu3' ]
     topo = TreeTopo( depth=3, fanout=3 )
-    net = MininetCluster( topo=topo, servers=servers,
+    net = MininetCluster( topo=topo, servers=servers, link=RemoteLink,
                           placement=SwitchBinPlacer )
     net.start()
     CLI( net )
     net.stop()
 
+
 if __name__ == '__main__':
     setLogLevel( 'info' )
     demo()
-

examples/clusterperf.py

@@ -0,0 +1,24 @@
+#!/usr/bin/env python
+
+"clusterperf.py compare the maximum throughput between SSH and GRE tunnels"
+
+from mininet.examples.cluster import RemoteSSHLink, RemoteGRELink, RemoteHost
+from mininet.net import Mininet
+from mininet.log import setLogLevel
+
+def perf(Link):
+    "Test connectivity nand performance over Link"
+    net = Mininet( host=RemoteHost, link=Link, waitConnected=True )
+    h1 = net.addHost( 'h1')
+    h2 = net.addHost( 'h2', server='ubuntu2' )
+    net.addLink( h1, h2 )
+    net.start()
+    net.pingAll()
+    net.iperf()
+    net.stop()
+
+
+if __name__ == '__main__':
+    setLogLevel('info')
+    perf( RemoteSSHLink )
+    perf( RemoteGRELink )

examples/consoles.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 consoles.py: bring up a bunch of miniature consoles on a virtual network
@@ -27,6 +27,7 @@ Bob Lantz, April 2010
 
 import re
 
+# pylint: disable=import-error
 from Tkinter import Frame, Button, Label, Text, Scrollbar, Canvas, Wm, READABLE
 
 from mininet.log import setLogLevel
@@ -34,6 +35,9 @@ from mininet.topolib import TreeNet
 from mininet.term import makeTerms, cleanUpScreens
 from mininet.util import quietRun
 
+# pylint: disable=too-many-arguments
+
+
 class Console( Frame ):
     "A simple console on a host."
 
@@ -65,7 +69,10 @@ class Console( Frame ):
         self.bindEvents()
         self.sendCmd( 'export TERM=dumb' )
 
-        self.outputHook = None
+        def outputHook( _obj, _text):
+            return True
+
+        self.outputHook = outputHook
 
     def makeWidgets( self ):
         "Make a label, a text area, and a scroll bar."
@@ -107,10 +114,8 @@ class Console( Frame ):
         self.text.insert( 'end', text )
         self.text.mark_set( 'insert', 'end' )
         self.text.see( 'insert' )
-        outputHook = lambda x, y: True  # make pylint happier
-        if self.outputHook:
-            outputHook = self.outputHook
-        outputHook( self, text )
+        if callable( self.outputHook ):
+            self.outputHook( self, text )
 
     def handleKey( self, event ):
         "If it's an interactive command, send it to the node."
@@ -290,10 +295,10 @@ class ConsoleApp( Frame ):
             'switches': 'Switch',
             'controllers': 'Controller'
         }
-        for name in titles:
+        for name, title in titles.items():
             nodes = getattr( net, name )
             frame, consoles = self.createConsoles(
-                cframe, nodes, width, titles[ name ] )
+                cframe, nodes, width, title )
             self.consoles[ name ] = Object( frame=frame, consoles=consoles )
         self.selected = None
         self.select( 'hosts' )
@@ -319,7 +324,7 @@ class ConsoleApp( Frame ):
         if not m:
             return
         val, units = float( m.group( 1 ) ), m.group( 2 )
-        #convert to Gbps
+        # convert to Gbps
         if units[0] == 'M':
             val *= 10 ** -3
         elif units[0] == 'K':
@@ -327,7 +332,7 @@ class ConsoleApp( Frame ):
         elif units[0] == 'b':
             val *= 10 ** -9
         self.updates += 1
-        self.bw +=  val
+        self.bw += val
         if self.updates >= self.hostCount:
             self.graph.addBar( self.bw )
             self.bw = 0

examples/controllers.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 Create a network where different switches are connected to
@@ -17,7 +17,7 @@ setLogLevel( 'info' )
 # Ignore the warning message that the remote isn't (yet) running
 c0 = Controller( 'c0', port=6633 )
 c1 = Controller( 'c1', port=6634 )
-c2 = RemoteController( 'c2', ip='127.0.0.1' )
+c2 = RemoteController( 'c2', ip='127.0.0.1', port=6633 )
 
 cmap = { 's1': c0, 's2': c1, 's3': c2 }
 
@@ -26,8 +26,9 @@ class MultiSwitch( OVSSwitch ):
     def start( self, controllers ):
         return OVSSwitch.start( self, [ cmap[ self.name ] ] )
 
+
 topo = TreeTopo( depth=2, fanout=2 )
-net = Mininet( topo=topo, switch=MultiSwitch, build=False )
+net = Mininet( topo=topo, switch=MultiSwitch, build=False, waitConnected=True )
 for c in [ c0, c1 ]:
     net.addController(c)
 net.build()

examples/controllers2.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 This example creates a multi-controller network from semi-scratch by
@@ -11,51 +11,54 @@ Note that one could also create a custom switch class and pass it into
 the Mininet() constructor.
 """
 
+
 from mininet.net import Mininet
 from mininet.node import Controller, OVSSwitch
 from mininet.cli import CLI
-from mininet.log import setLogLevel
+from mininet.log import setLogLevel, info
 
 def multiControllerNet():
     "Create a network from semi-scratch with multiple controllers."
 
-    net = Mininet( controller=Controller, switch=OVSSwitch )
+    net = Mininet( controller=Controller, switch=OVSSwitch,
+                   waitConnected=True )
 
-    print "*** Creating (reference) controllers"
+    info( "*** Creating (reference) controllers\n" )
     c1 = net.addController( 'c1', port=6633 )
     c2 = net.addController( 'c2', port=6634 )
 
-    print "*** Creating switches"
+    info( "*** Creating switches\n" )
     s1 = net.addSwitch( 's1' )
     s2 = net.addSwitch( 's2' )
 
-    print "*** Creating hosts"
-    hosts1 = [ net.addHost( 'h%d' % n ) for n in 3, 4 ]
-    hosts2 = [ net.addHost( 'h%d' % n ) for n in 5, 6 ]
+    info( "*** Creating hosts\n" )
+    hosts1 = [ net.addHost( 'h%d' % n ) for n in ( 3, 4 ) ]
+    hosts2 = [ net.addHost( 'h%d' % n ) for n in ( 5, 6 ) ]
 
-    print "*** Creating links"
+    info( "*** Creating links\n" )
     for h in hosts1:
         net.addLink( s1, h )
     for h in hosts2:
         net.addLink( s2, h )
     net.addLink( s1, s2 )
 
-    print "*** Starting network"
+    info( "*** Starting network\n" )
     net.build()
     c1.start()
     c2.start()
     s1.start( [ c1 ] )
     s2.start( [ c2 ] )
 
-    print "*** Testing network"
+    info( "*** Testing network\n" )
     net.pingAll()
 
-    print "*** Running CLI"
+    info( "*** Running CLI\n" )
     CLI( net )
 
-    print "*** Stopping network"
+    info( "*** Stopping network\n" )
     net.stop()
 
+
 if __name__ == '__main__':
     setLogLevel( 'info' )  # for CLI output
     multiControllerNet()

examples/controlnet.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 controlnet.py: Mininet with a custom control network
@@ -27,22 +27,29 @@ from mininet.log import setLogLevel, info
 
 class DataController( Controller ):
     """Data Network Controller.
-       patched to avoid checkListening error"""
+       patched to avoid checkListening error and to delete intfs"""
+
     def checkListening( self ):
         "Ignore spurious error"
         pass
 
+    def stop( self, *args, **kwargs ):
+        "Make sure intfs are deleted"
+        kwargs.update( deleteIntfs=True )
+        super( DataController, self ).stop( *args, **kwargs )
+
+
 class MininetFacade( object ):
     """Mininet object facade that allows a single CLI to
        talk to one or more networks"""
-    
+
     def __init__( self, net, *args, **kwargs ):
         """Create MininetFacade object.
            net: Primary Mininet object
            args: unnamed networks passed as arguments
            kwargs: named networks passed as arguments"""
         self.net = net
-        self.nets = [ net ] + list( args ) + kwargs.values()
+        self.nets = [ net ] + list( args ) + list( kwargs.values() )
         self.nameToNet = kwargs
         self.nameToNet['net'] = net
 
@@ -52,13 +59,14 @@ class MininetFacade( object ):
 
     def __getitem__( self, key ):
         "returns primary/named networks or node from any net"
-        #search kwargs for net named key
+        # search kwargs for net named key
         if key in self.nameToNet:
             return self.nameToNet[ key ]
-        #search each net for node named key
+        # search each net for node named key
         for net in self.nets:
             if key in net:
                 return net[ key ]
+        return None
 
     def __iter__( self ):
         "Iterate through all nodes in all Mininet objects"
@@ -93,10 +101,10 @@ class MininetFacade( object ):
 
 class ControlNetwork( Topo ):
     "Control Network Topology"
-    def __init__( self, n, dataController=DataController, **kwargs ):
+    # pylint: disable=arguments-differ
+    def build( self, n, dataController=DataController, **_kwargs ):
         """n: number of data network controller nodes
            dataController: class for data network controllers"""
-        Topo.__init__( self, **kwargs )
         # Connect everything to a single switch
         cs0 = self.addSwitch( 'cs0' )
         # Add hosts which will serve as data network controllers
@@ -114,10 +122,11 @@ class ControlNetwork( Topo ):
 
 def run():
     "Create control and data networks, and invoke the CLI"
-    
+
     info( '* Creating Control Network\n' )
     ctopo = ControlNetwork( n=4, dataController=DataController )
-    cnet = Mininet( topo=ctopo, ipBase='192.168.123.0/24', controller=None )
+    cnet = Mininet( topo=ctopo, ipBase='192.168.123.0/24',
+                    controller=None, waitConnected=True )
     info( '* Adding Control Network Controller\n')
     cnet.addController( 'cc0', controller=Controller )
     info( '* Starting Control Network\n')
@@ -127,7 +136,8 @@ def run():
     topo = TreeTopo( depth=2, fanout=2 )
     # UserSwitch so we can easily test failover
     sw = partial( UserSwitch, opts='--inactivity-probe=1 --max-backoff=1' )
-    net = Mininet( topo=topo, switch=sw, controller=None )
+    net = Mininet( topo=topo, switch=sw, controller=None,
+                   waitConnected=True )
     info( '* Adding Controllers to Data Network\n' )
     for host in cnet.hosts:
         if isinstance(host, Controller):

examples/cpu.py

@@ -1,18 +1,41 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 cpu.py: test iperf bandwidth for varying cpu limits
+
+Since we are limiting the hosts (only), we should expect the iperf
+processes to be affected, as well as any system processing which is
+billed to the hosts.
+
+We reserve >50% of cycles for system processing; we assume that
+this is enough for it not to affect results. Hosts are limited to
+40% of total cycles, which we assume is enough to make them CPU
+bound.
+
+As CPU performance increases over time, we may have to reduce the
+overall CPU allocation so that the host processing is still CPU bound.
+This is perhaps an argument for specifying performance in a more
+system-independent manner.
+
+It would also be nice to have a better handle on limiting packet
+processing cycles. It's not entirely clear to me how those are
+billed to user or system processes if we are using OVS with a kernel
+datapath. With a user datapath, they are easier to account for, but
+overall performance is usually lower.
+
+Although the iperf client uses more CPU and should be CPU bound (?),
+we measure the received data at the server since the client transmit
+rate includes buffering.
 """
 
 from mininet.net import Mininet
 from mininet.node import CPULimitedHost
 from mininet.topolib import TreeTopo
-from mininet.util import custom, waitListening
-from mininet.log import setLogLevel, output, info
+from mininet.util import custom, waitListening, decode
+from mininet.log import setLogLevel, info
+from mininet.clean import cleanup
 
-from time import sleep
-
-def bwtest( cpuLimits, period_us=100000, seconds=5 ):
+def bwtest( cpuLimits, period_us=100000, seconds=10 ):
     """Example/test of link and CPU bandwidth limits
        cpu: cpu limit as fraction of overall CPU time"""
 
@@ -21,26 +44,41 @@ def bwtest( cpuLimits, period_us=100000, seconds=5 ):
     results = {}
 
     for sched in 'rt', 'cfs':
-        print '*** Testing with', sched, 'bandwidth limiting'
+        info( '*** Testing with', sched, 'bandwidth limiting\n' )
         for cpu in cpuLimits:
+            # cpu is the cpu fraction for all hosts, so we divide
+            # it across two hosts
             host = custom( CPULimitedHost, sched=sched,
                            period_us=period_us,
-                           cpu=cpu )
+                           cpu=.5*cpu )
             try:
-                net = Mininet( topo=topo, host=host )
-            except:
-                info( '*** Skipping host %s\n' % sched )
+                net = Mininet( topo=topo, host=host, waitConnected=True )
+            # pylint: disable=bare-except
+            except:  # noqa
+                info( '*** Skipping scheduler %s and cleaning up\n' % sched )
+                cleanup()
                 break
             net.start()
             net.pingAll()
             hosts = [ net.getNodeByName( h ) for h in topo.hosts() ]
             client, server = hosts[ 0 ], hosts[ -1 ]
-            server.cmd( 'iperf -s -p 5001 &' )
+            info( '*** Starting iperf with %d%% of CPU allocated to hosts\n' %
+                  ( 100.0 * cpu ) )
+            # We measure at the server because it doesn't include
+            # the client's buffer fill rate
+            popen = server.popen( 'iperf -yc -s -p 5001' )
             waitListening( client, server, 5001 )
-            result = client.cmd( 'iperf -yc -t %s -c %s' % (
-                seconds, server.IP() ) ).split( ',' )
-            bps = float( result[ -1 ] )
-            server.cmdPrint( 'kill %iperf' )
+            client.cmd( 'iperf -yc -t %s -c %s' % ( seconds, server.IP() ) )
+            # ignore empty result from waitListening/telnet for old iperf
+            svals = {}
+            while not svals or int( svals[ 'rate' ] ) == 0:
+                line = decode( popen.stdout.readline() )
+                # Probably shouldn't depend on an internal method, but
+                # this is the easiest way
+                svals = Mininet._iperfVals(  # pylint: disable=protected-access
+                    line, server.IP() )
+            bps = float( svals[ 'rate' ] )
+            popen.terminate()
             net.stop()
             updated = results.get( sched, [] )
             updated += [ ( cpu, bps ) ]
@@ -52,22 +90,23 @@ def bwtest( cpuLimits, period_us=100000, seconds=5 ):
 def dump( results ):
     "Dump results"
 
-    fmt = '%s\t%s\t%s'
+    fmt = '%s\t%s\t%s\n'
 
-    print
-    print fmt % ( 'sched', 'cpu', 'client MB/s' )
-    print
+    info( '\n' )
+    info( fmt % ( 'sched', 'cpu', 'received bits/sec' ) )
 
     for sched in sorted( results.keys() ):
         entries = results[ sched ]
         for cpu, bps in entries:
-            pct = '%.2f%%' % ( cpu * 100 )
-            mbps = bps / 1e6
-            print fmt % ( sched, pct, mbps )
+            pct = '%d%%' % ( cpu * 100 )
+            mbps = '%.2e' % bps
+            info( fmt % ( sched, pct, mbps ) )
 
 
 if __name__ == '__main__':
     setLogLevel( 'info' )
-    limits = [ .45, .4, .3, .2, .1 ]
+    # These are the limits for the hosts/iperfs - the
+    # rest is for system processes
+    limits = [ .5, .4, .3, .2, .1 ]
     out = bwtest( limits )
     dump( out )

examples/emptynet.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 This example shows how to create an empty Mininet object
@@ -14,7 +14,7 @@ def emptyNet():
 
     "Create an empty network and add nodes to it."
 
-    net = Mininet( controller=Controller )
+    net = Mininet( controller=Controller, waitConnected=True )
 
     info( '*** Adding controller\n' )
     net.addController( 'c0' )
@@ -39,6 +39,7 @@ def emptyNet():
     info( '*** Stopping network' )
     net.stop()
 
+
 if __name__ == '__main__':
     setLogLevel( 'info' )
     emptyNet()

examples/hwintf.py

@@ -1,11 +1,14 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 This example shows how to add an interface (for example a real
 hardware interface) to a network after the network is created.
 """
 
-import re, sys
+import re
+import sys
+
+from sys import exit  # pylint: disable=redefined-builtin
 
 from mininet.cli import CLI
 from mininet.log import setLogLevel, info, error
@@ -14,17 +17,20 @@ from mininet.link import Intf
 from mininet.topolib import TreeTopo
 from mininet.util import quietRun
 
+
 def checkIntf( intf ):
     "Make sure intf exists and is not configured."
-    if ( ' %s:' % intf ) not in quietRun( 'ip link show' ):
+    config = quietRun( 'ifconfig %s 2>/dev/null' % intf, shell=True )
+    if not config:
         error( 'Error:', intf, 'does not exist!\n' )
         exit( 1 )
-    ips = re.findall( r'\d+\.\d+\.\d+\.\d+', quietRun( 'ifconfig ' + intf ) )
+    ips = re.findall( r'\d+\.\d+\.\d+\.\d+', config )
     if ips:
         error( 'Error:', intf, 'has an IP address,'
                'and is probably in use!\n' )
         exit( 1 )
 
+
 if __name__ == '__main__':
     setLogLevel( 'info' )
 
@@ -36,7 +42,7 @@ if __name__ == '__main__':
     checkIntf( intfName )
 
     info( '*** Creating network\n' )
-    net = Mininet( topo=TreeTopo( depth=1, fanout=2 ) )
+    net = Mininet( topo=TreeTopo( depth=1, fanout=2 ), waitConnected=True )
 
     switch = net.switches[ 0 ]
     info( '*** Adding hardware interface', intfName, 'to switch',

examples/intfoptions.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 '''
 example of using various TCIntf options.
@@ -13,36 +13,37 @@ from mininet.link import TCLink
 
 def intfOptions():
     "run various traffic control commands on a single interface"
-    net = Mininet( autoStaticArp=True )
+    net = Mininet( autoStaticArp=True, waitConnected=True )
     net.addController( 'c0' )
     h1 = net.addHost( 'h1' )
     h2 = net.addHost( 'h2' )
     s1 = net.addSwitch( 's1' )
     link1 = net.addLink( h1, s1, cls=TCLink )
-    link2 = net.addLink( h2, s1 )
+    net.addLink( h2, s1 )
     net.start()
-    
+
     # flush out latency from reactive forwarding delay
     net.pingAll()
 
-    info( '\n*** Configuring one intf with bandwidth of 5 Mb\n' )
-    link1.intf1.config( bw=5 )
+    info( '\n*** Configuring one intf with bandwidth of 10 Mb\n' )
+    link1.intf1.config( bw=10 )
     info( '\n*** Running iperf to test\n' )
-    net.iperf()
+    net.iperf( seconds=10 )
 
     info( '\n*** Configuring one intf with loss of 50%\n' )
     link1.intf1.config( loss=50 )
     info( '\n' )
     net.iperf( ( h1, h2 ), l4Type='UDP' )
-    
+
     info( '\n*** Configuring one intf with delay of 15ms\n' )
     link1.intf1.config( delay='15ms' )
     info( '\n*** Run a ping to confirm delay\n' )
     net.pingPairFull()
-    
+
     info( '\n*** Done testing\n' )
     net.stop()
 
+
 if __name__ == '__main__':
     setLogLevel( 'info' )
     intfOptions()

examples/limit.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 limit.py: example of using link and CPU limits
@@ -27,12 +27,14 @@ def limit( bw=10, cpu=.1 ):
         info( '*** Testing with', sched, 'bandwidth limiting\n' )
         if sched == 'rt':
             release = quietRun( 'uname -r' ).strip('\r\n')
-            output = quietRun( 'grep CONFIG_RT_GROUP_SCHED /boot/config-%s' % release )
+            output = quietRun( 'grep CONFIG_RT_GROUP_SCHED /boot/config-%s'
+                               % release )
             if output == '# CONFIG_RT_GROUP_SCHED is not set\n':
-                info( '*** RT Scheduler is not enabled in your kernel. Skipping this test\n' )
+                info( '*** RT Scheduler is not enabled in your kernel. '
+                      'Skipping this test\n' )
                 continue
         host = custom( CPULimitedHost, sched=sched, cpu=cpu )
-        net = Mininet( topo=myTopo, intf=intf, host=host )
+        net = Mininet( topo=myTopo, intf=intf, host=host, waitConnected=True )
         net.start()
         testLinkLimit( net, bw=bw )
         net.runCpuLimitTest( cpu=cpu )
@@ -41,7 +43,7 @@ def limit( bw=10, cpu=.1 ):
 def verySimpleLimit( bw=150 ):
     "Absurdly simple limiting test"
     intf = custom( TCIntf, bw=bw )
-    net = Mininet( intf=intf )
+    net = Mininet( intf=intf, waitConnected=True )
     h1, h2 = net.addHost( 'h1' ), net.addHost( 'h2' )
     net.addLink( h1, h2 )
     net.start()
@@ -53,6 +55,7 @@ def verySimpleLimit( bw=150 ):
     h2.cmdPrint( 'tc -d class show dev', h2.defaultIntf() )
     net.stop()
 
+
 if __name__ == '__main__':
     setLogLevel( 'info' )
     limit()

examples/linearbandwidth.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 Test bandwidth (using iperf) on linear networks of varying size,
@@ -23,25 +23,26 @@ of switches, this example demonstrates:
 
 """
 
+
+import sys
+
+from functools import partial
+
 from mininet.net import Mininet
 from mininet.node import UserSwitch, OVSKernelSwitch, Controller
 from mininet.topo import Topo
-from mininet.log import lg
-from mininet.util import irange
+from mininet.log import lg, info
+from mininet.util import irange, quietRun
 from mininet.link import TCLink
-from functools import partial
 
-import sys
 flush = sys.stdout.flush
 
+
 class LinearTestTopo( Topo ):
     "Topology for a string of N hosts and N-1 switches."
 
-    def __init__( self, N, **params ):
-
-        # Initialize topology
-        Topo.__init__( self, **params )
-
+    # pylint: disable=arguments-differ
+    def build( self, N, **params ):
         # Create switches and hosts
         hosts = [ self.addHost( 'h%s' % h )
                   for h in irange( 1, N ) ]
@@ -78,45 +79,48 @@ def linearBandwidthTest( lengths ):
 
     topo = LinearTestTopo( hostCount )
 
-    for datapath in switches.keys():
-        print "*** testing", datapath, "datapath"
-        Switch = switches[ datapath ]
+    # Select TCP Reno
+    output = quietRun( 'sysctl -w net.ipv4.tcp_congestion_control=reno' )
+    assert 'reno' in output
+
+    for datapath, Switch in switches.items():
+        info( "*** testing", datapath, "datapath\n" )
         results[ datapath ] = []
-        link = partial( TCLink, delay='1ms' )
+        link = partial( TCLink, delay='30ms', bw=100 )
         net = Mininet( topo=topo, switch=Switch,
-                       controller=Controller, waitConnected=True,
-                       link=link )
+                       controller=Controller, link=link,
+                       waitConnected=True )
         net.start()
-        print "*** testing basic connectivity"
+        info( "*** testing basic connectivity\n" )
         for n in lengths:
             net.ping( [ net.hosts[ 0 ], net.hosts[ n ] ] )
-        print "*** testing bandwidth"
+        info( "*** testing bandwidth\n" )
         for n in lengths:
             src, dst = net.hosts[ 0 ], net.hosts[ n ]
             # Try to prime the pump to reduce PACKET_INs during test
             # since the reference controller is reactive
             src.cmd( 'telnet', dst.IP(), '5001' )
-            print "testing", src.name, "<->", dst.name,
-            bandwidth = net.iperf( [ src, dst ] )
-            print bandwidth
+            info( "testing", src.name, "<->", dst.name, '\n' )
+            # serverbw = received; _clientbw = buffered
+            serverbw, _clientbw = net.iperf( [ src, dst ], seconds=5 )
+            info( serverbw, '\n' )
             flush()
-            results[ datapath ] += [ ( n, bandwidth ) ]
+            results[ datapath ] += [ ( n, serverbw ) ]
         net.stop()
 
-    for datapath in switches.keys():
-        print
-        print "*** Linear network results for", datapath, "datapath:"
-        print
+    for datapath in switches:
+        info( "\n*** Linear network results for", datapath, "datapath:\n" )
         result = results[ datapath ]
-        print "SwitchCount\tiperf Results"
-        for switchCount, bandwidth in result:
-            print switchCount, '\t\t',
-            print bandwidth[ 0 ], 'server, ', bandwidth[ 1 ], 'client'
-        print
-    print
+        info( "SwitchCount\tiperf Results\n" )
+        for switchCount, serverbw in result:
+            info( switchCount, '\t\t' )
+            info( serverbw, '\n' )
+        info( '\n')
+    info( '\n' )
+
 
 if __name__ == '__main__':
     lg.setLogLevel( 'info' )
-    sizes = [ 1, 10, 20, 40, 60, 80, 100 ]
-    print "*** Running linearBandwidthTest", sizes
+    sizes = [ 1, 2, 3, 4 ]
+    info( "*** Running linearBandwidthTest", sizes, '\n' )
     linearBandwidthTest( sizes  )

examples/linuxrouter.py

@@ -1,37 +1,44 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 linuxrouter.py: Example network with Linux IP router
- 
+
 This example converts a Node into a router using IP forwarding
 already built into Linux.
 
-The topology contains a router with three IP subnets:
- - 192.168.1.0/24 (interface IP: 192.168.1.1)
- - 172.16.0.0/12 (interface IP: 172.16.0.1)
- - 10.0.0.0/8 (interface IP: 10.0.0.1)
+The example topology creates a router and three IP subnets:
 
- It also contains three hosts, one in each subnet:
- - h1 (IP: 192.168.1.100)
- - h2 (IP: 172.16.0.100)
- - h3 (IP: 10.0.0.100)
+    - 192.168.1.0/24 (r0-eth1, IP: 192.168.1.1)
+    - 172.16.0.0/12 (r0-eth2, IP: 172.16.0.1)
+    - 10.0.0.0/8 (r0-eth3, IP: 10.0.0.1)
 
- Routing entries can be added to the routing tables of the 
- hosts or router using the "ip route add" or "route add" command.
- See the man pages for more details.
+Each subnet consists of a single host connected to
+a single switch:
 
+    r0-eth1 - s1-eth1 - h1-eth0 (IP: 192.168.1.100)
+    r0-eth2 - s2-eth1 - h2-eth0 (IP: 172.16.0.100)
+    r0-eth3 - s3-eth1 - h3-eth0 (IP: 10.0.0.100)
+
+The example relies on default routing entries that are
+automatically created for each router interface, as well
+as 'defaultRoute' parameters for the host interfaces.
+
+Additional routes may be added to the router or hosts by
+executing 'ip route' or 'route' commands on the router or hosts.
 """
 
+
 from mininet.topo import Topo
 from mininet.net import Mininet
 from mininet.node import Node
 from mininet.log import setLogLevel, info
 from mininet.cli import CLI
-from mininet.util import irange
+
 
 class LinuxRouter( Node ):
     "A Node with IP forwarding enabled."
 
+    # pylint: disable=arguments-differ
     def config( self, **params ):
         super( LinuxRouter, self).config( **params )
         # Enable forwarding on the router
@@ -43,26 +50,46 @@ class LinuxRouter( Node ):
 
 
 class NetworkTopo( Topo ):
-    "A simple topology of a router with three subnets (one host in each)."
+    "A LinuxRouter connecting three IP subnets"
+
+    # pylint: disable=arguments-differ
+    def build( self, **_opts ):
+
+        defaultIP = '192.168.1.1/24'  # IP address for r0-eth1
+        router = self.addNode( 'r0', cls=LinuxRouter, ip=defaultIP )
+
+        s1, s2, s3 = [ self.addSwitch( s ) for s in ( 's1', 's2', 's3' ) ]
+
+        self.addLink( s1, router, intfName2='r0-eth1',
+                      params2={ 'ip' : defaultIP } )  # for clarity
+        self.addLink( s2, router, intfName2='r0-eth2',
+                      params2={ 'ip' : '172.16.0.1/12' } )
+        self.addLink( s3, router, intfName2='r0-eth3',
+                      params2={ 'ip' : '10.0.0.1/8' } )
+
+        h1 = self.addHost( 'h1', ip='192.168.1.100/24',
+                           defaultRoute='via 192.168.1.1' )
+        h2 = self.addHost( 'h2', ip='172.16.0.100/12',
+                           defaultRoute='via 172.16.0.1' )
+        h3 = self.addHost( 'h3', ip='10.0.0.100/8',
+                           defaultRoute='via 10.0.0.1' )
+
+        for h, s in [ (h1, s1), (h2, s2), (h3, s3) ]:
+            self.addLink( h, s )
 
-    def build( self, n=2, h=1, **opts ):
-        router = self.addNode( 'r0', cls=LinuxRouter, ip='192.168.1.1/24' )
-        h1 = self.addHost( 'h1', ip='192.168.1.100/24', defaultRoute='via 192.168.1.1' )
-        h2 = self.addHost( 'h2', ip='172.16.0.100/12', defaultRoute='via 172.16.0.1' )
-        h3 = self.addHost( 'h3', ip='10.0.0.100/8', defaultRoute='via 10.0.0.1' )
-        self.addLink( h1, router, intfName2='r0-eth1', params2={ 'ip' : '192.168.1.1/24' } )
-        self.addLink( h2, router, intfName2='r0-eth2', params2={ 'ip' : '172.16.0.1/12' } )
-        self.addLink( h3, router, intfName2='r0-eth3', params2={ 'ip' : '10.0.0.1/8' } )
 
 def run():
+    "Test linux router"
     topo = NetworkTopo()
-    net = Mininet( topo=topo, controller=None ) # no controller needed
+    net = Mininet( topo=topo,
+                   waitConnected=True )  # controller is used by s1-s3
     net.start()
-    info( '*** Routing Table on Router\n' )
-    print net[ 'r0' ].cmd( 'route' )
+    info( '*** Routing Table on Router:\n' )
+    info( net[ 'r0' ].cmd( 'route' ) )
     CLI( net )
     net.stop()
 
+
 if __name__ == '__main__':
     setLogLevel( 'info' )
     run()

examples/mobility.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 Simple example of Mobility with Mininet
@@ -19,14 +19,12 @@ to-do:
 - think about clearing last hop - why doesn't that work?
 """
 
+from random import randint
+
 from mininet.net import Mininet
 from mininet.node import OVSSwitch
 from mininet.topo import LinearTopo
-from mininet.util import quietRun
-from mininet.log import output, warn
-
-from random import randint
-from re import findall
+from mininet.log import info, output, warn, setLogLevel
 
 
 class MobilitySwitch( OVSSwitch ):
@@ -39,6 +37,7 @@ class MobilitySwitch( OVSSwitch ):
         del self.intfs[ port ]
         del self.nameToIntf[ intf.name ]
 
+    # pylint: disable=arguments-differ
     def addIntf( self, intf, rename=False, **kwargs ):
         "Add (and reparent) an interface"
         OVSSwitch.addIntf( self, intf, **kwargs )
@@ -61,7 +60,7 @@ class MobilitySwitch( OVSSwitch ):
     def validatePort( self, intf ):
         "Validate intf's OF port number"
         ofport = int( self.cmd( 'ovs-vsctl get Interface', intf,
-                              'ofport' ) )
+                                'ofport' ) )
         if ofport != self.ports[ intf ]:
             warn( 'WARNING: ofport for', intf, 'is actually', ofport,
                   '\n' )
@@ -107,30 +106,33 @@ def moveHost( host, oldSwitch, newSwitch, newPort=None ):
 
 def mobilityTest():
     "A simple test of mobility"
-    print '* Simple mobility test'
-    net = Mininet( topo=LinearTopo( 3 ), switch=MobilitySwitch )
-    print '* Starting network:'
+    info( '* Simple mobility test\n' )
+    net = Mininet( topo=LinearTopo( 3 ), switch=MobilitySwitch,
+                                    waitConnected=True )
+    info( '* Starting network:\n' )
     net.start()
     printConnections( net.switches )
-    print '* Testing network'
+    info( '* Testing network\n' )
     net.pingAll()
-    print '* Identifying switch interface for h1'
+    info( '* Identifying switch interface for h1\n' )
     h1, old = net.get( 'h1', 's1' )
     for s in 2, 3, 1:
         new = net[ 's%d' % s ]
         port = randint( 10, 20 )
-        print '* Moving', h1, 'from', old, 'to', new, 'port', port
+        info( '* Moving', h1, 'from', old, 'to', new, 'port', port, '\n' )
         hintf, sintf = moveHost( h1, old, new, newPort=port )
-        print '*', hintf, 'is now connected to', sintf
-        print '* Clearing out old flows'
+        info( '*', hintf, 'is now connected to', sintf, '\n' )
+        info( '* Clearing out old flows\n' )
         for sw in net.switches:
             sw.dpctl( 'del-flows' )
-        print '* New network:'
+        info( '* New network:\n' )
         printConnections( net.switches )
-        print '* Testing connectivity:'
+        info( '* Testing connectivity:\n' )
         net.pingAll()
         old = new
     net.stop()
 
+
 if __name__ == '__main__':
+    setLogLevel( 'info' )
     mobilityTest()

examples/multilink.py

@@ -0,0 +1,36 @@
+#!/usr/bin/env python
+
+"""
+This is a simple example that demonstrates multiple links
+between nodes.
+"""
+
+from mininet.cli import CLI
+from mininet.log import setLogLevel
+from mininet.net import Mininet
+from mininet.topo import Topo
+
+def runMultiLink():
+    "Create and run multiple link network"
+    topo = simpleMultiLinkTopo( n=2 )
+    net = Mininet( topo=topo, waitConnected=True )
+    net.start()
+    CLI( net )
+    net.stop()
+
+class simpleMultiLinkTopo( Topo ):
+    "Simple topology with multiple links"
+
+    # pylint: disable=arguments-differ
+    def build( self, n, **_kwargs ):
+        h1, h2 = self.addHost( 'h1' ), self.addHost( 'h2' )
+        s1 = self.addSwitch( 's1' )
+
+        for _ in range( n ):
+            self.addLink( s1, h1 )
+            self.addLink( s1, h2 )
+
+
+if __name__ == '__main__':
+    setLogLevel( 'info' )
+    runMultiLink()

examples/multiping.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 multiping.py: monitor multiple sets of hosts using ping
@@ -8,17 +8,18 @@ multiple hosts and monitor their output interactively for a period=
 of time.
 """
 
-from mininet.net import Mininet
-from mininet.node import Node
-from mininet.topo import SingleSwitchTopo
-from mininet.log import setLogLevel
-
 from select import poll, POLLIN
 from time import time
 
-def chunks( l, n ):
+from mininet.net import Mininet
+from mininet.node import Node
+from mininet.topo import SingleSwitchTopo
+from mininet.log import info, setLogLevel
+
+
+def chunks( items, n ):
     "Divide list l into chunks of size n - thanks Stackoverflow"
-    return [ l[ i: i + n ] for i in range( 0, len( l ), n ) ]
+    return [ items[ i: i + n ] for i in range( 0, len( items ), n ) ]
 
 def startpings( host, targetips ):
     "Tell host to repeatedly ping targets"
@@ -34,8 +35,8 @@ def startpings( host, targetips ):
             ' done; '
             'done &' )
 
-    print ( '*** Host %s (%s) will be pinging ips: %s' %
-            ( host.name, host.IP(), targetips ) )
+    info( '*** Host %s (%s) will be pinging ips: %s\n' %
+          ( host.name, host.IP(), targetips ) )
 
     host.cmd( cmd )
 
@@ -44,7 +45,7 @@ def multiping( netsize, chunksize, seconds):
 
     # Create network and identify subnets
     topo = SingleSwitchTopo( netsize )
-    net = Mininet( topo=topo )
+    net = Mininet( topo=topo, waitConnected=True )
     net.start()
     hosts = net.hosts
     subnets = chunks( hosts, chunksize )
@@ -58,7 +59,7 @@ def multiping( netsize, chunksize, seconds):
     # Start pings
     for subnet in subnets:
         ips = [ host.IP() for host in subnet ]
-        #adding bogus to generate packet loss
+        # adding bogus to generate packet loss
         ips.append( '10.0.0.200' )
         for host in subnet:
             startpings( host, ips )
@@ -69,7 +70,7 @@ def multiping( netsize, chunksize, seconds):
         readable = poller.poll(1000)
         for fd, _mask in readable:
             node = Node.outToNode[ fd ]
-            print '%s:' % node.name, node.monitor().strip()
+            info( '%s:' % node.name, node.monitor().strip(), '\n' )
 
     # Stop pings
     for host in hosts:

examples/multipoll.py

@@ -1,25 +1,29 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 Simple example of sending output to multiple files and
 monitoring them
 """
 
-from mininet.topo import SingleSwitchTopo
-from mininet.net import Mininet
-from mininet.log import setLogLevel
 
 from time import time
 from select import poll, POLLIN
 from subprocess import Popen, PIPE
 
+from mininet.topo import SingleSwitchTopo
+from mininet.net import Mininet
+from mininet.log import info, setLogLevel
+from mininet.util import decode
+
+
 def monitorFiles( outfiles, seconds, timeoutms ):
     "Monitor set of files and return [(host, line)...]"
-    devnull = open( '/dev/null', 'w' )
+    devnull = open( '/dev/null', 'w' )  # pylint: disable=consider-using-with
     tails, fdToFile, fdToHost = {}, {}, {}
-    for h, outfile in outfiles.iteritems():
-        tail = Popen( [ 'tail', '-f', outfile ],
-                      stdout=PIPE, stderr=devnull )
+    for h, outfile in outfiles.items():
+        tail = Popen(  # pylint: disable=consider-using-with
+            [ 'tail', '-f', outfile ],
+            stdout=PIPE, stderr=devnull )
         fd = tail.stdout.fileno()
         tails[ h ] = tail
         fdToFile[ fd ] = tail.stdout
@@ -38,7 +42,7 @@ def monitorFiles( outfiles, seconds, timeoutms ):
                 host = fdToHost[ fd ]
                 # Wait for a line of output
                 line = f.readline().strip()
-                yield host, line
+                yield host, decode( line )
         else:
             # If we timed out, return nothing
             yield None, ''
@@ -50,10 +54,10 @@ def monitorFiles( outfiles, seconds, timeoutms ):
 def monitorTest( N=3, seconds=3 ):
     "Run pings and monitor multiple hosts"
     topo = SingleSwitchTopo( N )
-    net = Mininet( topo )
+    net = Mininet( topo, waitConnected=True )
     net.start()
     hosts = net.hosts
-    print "Starting test..."
+    info( "Starting test...\n" )
     server = hosts[ 0 ]
     outfiles, errfiles = {}, {}
     for h in hosts:
@@ -67,10 +71,10 @@ def monitorTest( N=3, seconds=3 ):
                    '>', outfiles[ h ],
                    '2>', errfiles[ h ],
                    '&' )
-    print "Monitoring output for", seconds, "seconds"
+    info( "Monitoring output for", seconds, "seconds\n" )
     for h, line in monitorFiles( outfiles, seconds, timeoutms=500 ):
         if h:
-            print '%s: %s' % ( h.name, line )
+            info( '%s: %s\n' % ( h.name, line ) )
     for h in hosts:
         h.cmd('kill %ping')
     net.stop()

examples/multitest.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 This example shows how to create a network and run multiple tests.
@@ -17,12 +17,14 @@ def ifconfigTest( net ):
     for host in hosts:
         info( host.cmd( 'ifconfig' ) )
 
+
 if __name__ == '__main__':
     lg.setLogLevel( 'info' )
     info( "*** Initializing Mininet and kernel modules\n" )
     OVSKernelSwitch.setup()
     info( "*** Creating network\n" )
-    network = Mininet( TreeTopo( depth=2, fanout=2 ), switch=OVSKernelSwitch )
+    network = Mininet( TreeTopo( depth=2, fanout=2), switch=OVSKernelSwitch,
+                       waitConnected=True )
     info( "*** Starting network\n" )
     network.start()
     info( "*** Running ping test\n" )

examples/nat.py

@@ -1,112 +1,23 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 Example to create a Mininet topology and connect it to the internet via NAT
-through eth0 on the host.
-
-Glen Gibb, February 2011
-
-(slight modifications by BL, 5/13)
 """
 
+
 from mininet.cli import CLI
-from mininet.log import lg
-from mininet.node import Node
+from mininet.log import lg, info
 from mininet.topolib import TreeNet
 
-#################################
-def startNAT( root, inetIntf='eth0', subnet='10.0/8' ):
-    """Start NAT/forwarding between Mininet and external network
-    root: node to access iptables from
-    inetIntf: interface for internet access
-    subnet: Mininet subnet (default 10.0/8)="""
-
-    # Identify the interface connecting to the mininet network
-    localIntf =  root.defaultIntf()
-
-    # Flush any currently active rules
-    root.cmd( 'iptables -F' )
-    root.cmd( 'iptables -t nat -F' )
-
-    # Create default entries for unmatched traffic
-    root.cmd( 'iptables -P INPUT ACCEPT' )
-    root.cmd( 'iptables -P OUTPUT ACCEPT' )
-    root.cmd( 'iptables -P FORWARD DROP' )
-
-    # Configure NAT
-    root.cmd( 'iptables -I FORWARD -i', localIntf, '-d', subnet, '-j DROP' )
-    root.cmd( 'iptables -A FORWARD -i', localIntf, '-s', subnet, '-j ACCEPT' )
-    root.cmd( 'iptables -A FORWARD -i', inetIntf, '-d', subnet, '-j ACCEPT' )
-    root.cmd( 'iptables -t nat -A POSTROUTING -o ', inetIntf, '-j MASQUERADE' )
-
-    # Instruct the kernel to perform forwarding
-    root.cmd( 'sysctl net.ipv4.ip_forward=1' )
-
-def stopNAT( root ):
-    """Stop NAT/forwarding between Mininet and external network"""
-    # Flush any currently active rules
-    root.cmd( 'iptables -F' )
-    root.cmd( 'iptables -t nat -F' )
-
-    # Instruct the kernel to stop forwarding
-    root.cmd( 'sysctl net.ipv4.ip_forward=0' )
-
-def fixNetworkManager( root, intf ):
-    """Prevent network-manager from messing with our interface,
-       by specifying manual configuration in /etc/network/interfaces
-       root: a node in the root namespace (for running commands)
-       intf: interface name"""
-    cfile = '/etc/network/interfaces'
-    line = '\niface %s inet manual\n' % intf
-    config = open( cfile ).read()
-    if line not in config:
-        print '*** Adding', line.strip(), 'to', cfile
-        with open( cfile, 'a' ) as f:
-            f.write( line )
-        # Probably need to restart network-manager to be safe -
-        # hopefully this won't disconnect you
-        root.cmd( 'service network-manager restart' )
-
-def connectToInternet( network, switch='s1', rootip='10.254', subnet='10.0/8'):
-    """Connect the network to the internet
-       switch: switch to connect to root namespace
-       rootip: address for interface in root namespace
-       subnet: Mininet subnet"""
-    switch = network.get( switch )
-    prefixLen = subnet.split( '/' )[ 1 ]
-
-    # Create a node in root namespace
-    root = Node( 'root', inNamespace=False )
-
-    # Prevent network-manager from interfering with our interface
-    fixNetworkManager( root, 'root-eth0' )
-
-    # Create link between root NS and switch
-    link = network.addLink( root, switch )
-    link.intf1.setIP( rootip, prefixLen )
-
-    # Start network that now includes link to root namespace
-    network.start()
-
-    # Start NAT and establish forwarding
-    startNAT( root )
-
-    # Establish routes from end hosts
-    for host in network.hosts:
-        host.cmd( 'ip route flush root 0/0' )
-        host.cmd( 'route add -net', subnet, 'dev', host.defaultIntf() )
-        host.cmd( 'route add default gw', rootip )
-
-    return root
 
 if __name__ == '__main__':
     lg.setLogLevel( 'info')
-    net = TreeNet( depth=1, fanout=4 )
-    # Configure and start NATted connectivity
-    rootnode = connectToInternet( net )
-    print "*** Hosts are running and should have internet connectivity"
-    print "*** Type 'exit' or control-D to shut down network"
+    net = TreeNet( depth=1, fanout=4, waitConnected=True )
+    # Add NAT connectivity
+    net.addNAT().configDefault()
+    net.start()
+    info( "*** Hosts are running and should have internet connectivity\n" )
+    info( "*** Type 'exit' or control-D to shut down network\n" )
     CLI( net )
     # Shut down NAT
-    stopNAT( rootnode )
     net.stop()

examples/natnet.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 natnet.py: Example network with NATs
@@ -14,7 +14,7 @@ natnet.py: Example network with NATs
     |              |
    s1              s2
     |              |
-   h1              h2 
+   h1              h2
 
 """
 
@@ -27,9 +27,8 @@ from mininet.util import irange
 
 class InternetTopo(Topo):
     "Single switch connected to n hosts."
-    def __init__(self, n=2, h=1, **opts):
-        Topo.__init__(self, **opts)
-
+    # pylint: disable=arguments-differ
+    def build(self, n=2, **_kwargs ):
         # set up inet switch
         inetSwitch = self.addSwitch('s0')
         # add inet host
@@ -44,27 +43,27 @@ class InternetTopo(Topo):
             localSubnet = '192.168.%d.0/24' % i
             natParams = { 'ip' : '%s/24' % localIP }
             # add NAT to topology
-            nat = self.addNode('nat%d' % i, cls=NAT, subnet=localSubnet, 
+            nat = self.addNode('nat%d' % i, cls=NAT, subnet=localSubnet,
                                inetIntf=inetIntf, localIntf=localIntf)
             switch = self.addSwitch('s%d' % i)
             # connect NAT to inet and local switches
             self.addLink(nat, inetSwitch, intfName1=inetIntf)
             self.addLink(nat, switch, intfName1=localIntf, params1=natParams)
             # add host and connect to local switch
-            host = self.addHost('h%d' % i, 
-                                ip='192.168.%d.100/24' % i, 
+            host = self.addHost('h%d' % i,
+                                ip='192.168.%d.100/24' % i,
                                 defaultRoute='via %s' % localIP)
             self.addLink(host, switch)
 
 def run():
     "Create network and run the CLI"
     topo = InternetTopo()
-    net = Mininet(topo=topo)
+    net = Mininet(topo=topo, waitConnected=True )
     net.start()
     CLI(net)
     net.stop()
 
+
 if __name__ == '__main__':
     setLogLevel('info')
     run()
-    

examples/numberedports.py

@@ -1,31 +1,34 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
-Create a network with 5 hosts, numbered 1-4 and 9. 
+Create a network with 5 hosts, numbered 1-4 and 9.
 Validate that the port numbers match to the interface name,
 and that the ovs ports match the mininet ports.
 """
 
+
 from mininet.net import Mininet
 from mininet.node import Controller
 from mininet.log import setLogLevel, info, warn
-from mininet.node import Node
 
 def validatePort( switch, intf ):
     "Validate intf's OF port number"
     ofport = int( switch.cmd( 'ovs-vsctl get Interface', intf,
-                          'ofport' ) )
+                              'ofport' ) )
     if ofport != switch.ports[ intf ]:
         warn( 'WARNING: ofport for', intf, 'is actually', ofport, '\n' )
         return 0
     else:
         return 1
 
-def net():
+def testPortNumbering():
 
-    "Create a network with 5 hosts."
+    """Test port numbering:
+       Create a network with 5 hosts (using Mininet's
+       mid-level API) and check that implicit and
+       explicit port numbering works as expected."""
 
-    net = Mininet( controller=Controller )
+    net = Mininet( controller=Controller, waitConnected=True )
 
     info( '*** Adding controller\n' )
     net.addController( 'c0' )
@@ -46,31 +49,33 @@ def net():
     net.addLink( h2, s1 )
     net.addLink( h3, s1 )
     net.addLink( h4, s1 )
-    net.addLink( h5, s1, port1 = 1, port2 = 9 ) # specify a different port to connect host 5 to on the switch.
+    # specify a different port to connect host 5 to on the switch.
+    net.addLink( h5, s1, port1=1, port2= 9)
 
-    root = Node( 'root', inNamespace=False )
     info( '*** Starting network\n' )
     net.start()
 
     # print the interfaces and their port numbers
-    info( '\n*** printing and validating the ports running on each interface\n' )
+    info( '\n*** printing and validating the ports '
+          'running on each interface\n' )
     for intfs in s1.intfList():
         if not intfs.name == "lo":
-            info( intfs, ': ', s1.ports[intfs], 
-            '\n' )
-            info ( 'Validating that', intfs, 'is actually on port', s1.ports[intfs], '... ' )
+            info( intfs, ': ', s1.ports[intfs],
+                  '\n' )
+            info( 'Validating that', intfs,
+                   'is actually on port', s1.ports[intfs], '... ' )
             if validatePort( s1, intfs ):
                 info( 'Validated.\n' )
-    print '\n'
-        
+    info( '\n' )
+
     # test the network with pingall
     net.pingAll()
-    print '\n'
+    info( '\n' )
 
-    info( '*** Stopping network' )
+    info( '*** Stopping network\n' )
     net.stop()
 
+
 if __name__ == '__main__':
     setLogLevel( 'info' )
-    net()
-
+    testPortNumbering()

examples/popen.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 This example monitors a number of hosts using host.popen() and
@@ -6,17 +6,14 @@ pmonitor()
 """
 
 from mininet.net import Mininet
-from mininet.node import CPULimitedHost
 from mininet.topo import SingleSwitchTopo
-from mininet.log import setLogLevel
-from mininet.util import custom, pmonitor
+from mininet.log import setLogLevel, info
+from mininet.util import pmonitor
 
-def monitorhosts( hosts=5, sched='cfs' ):
+def monitorhosts( hosts=5 ):
     "Start a bunch of pings and monitor them using popen"
     mytopo = SingleSwitchTopo( hosts )
-    cpu = .5 / hosts
-    myhost = custom( CPULimitedHost, cpu=cpu, sched=sched )
-    net = Mininet( topo=mytopo, host=myhost )
+    net = Mininet( topo=mytopo, waitConnected=True )
     net.start()
     # Start a bunch of pings
     popens = {}
@@ -27,10 +24,11 @@ def monitorhosts( hosts=5, sched='cfs' ):
     # Monitor them and print output
     for host, line in pmonitor( popens ):
         if host:
-            print "<%s>: %s" % ( host.name, line.strip() )
+            info( "<%s>: %s" % ( host.name, line ) )
     # Done
     net.stop()
 
+
 if __name__ == '__main__':
     setLogLevel( 'info' )
     monitorhosts( hosts=5 )

examples/popenpoll.py

@@ -1,33 +1,38 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 "Monitor multiple hosts using popen()/pmonitor()"
 
+from time import time
+from signal import SIGINT
+
 from mininet.net import Mininet
 from mininet.topo import SingleSwitchTopo
 from mininet.util import pmonitor
-from time import time
-from signal import SIGINT
+from mininet.log import setLogLevel, info
+
 
 def pmonitorTest( N=3, seconds=10 ):
     "Run pings and monitor multiple hosts using pmonitor"
     topo = SingleSwitchTopo( N )
-    net = Mininet( topo )
+    net = Mininet( topo, waitConnected=True )
     net.start()
     hosts = net.hosts
-    print "Starting test..."
+    info( "Starting test...\n" )
     server = hosts[ 0 ]
     popens = {}
     for h in hosts:
         popens[ h ] = h.popen('ping', server.IP() )
-    print "Monitoring output for", seconds, "seconds"
+    info( "Monitoring output for", seconds, "seconds\n" )
     endTime = time() + seconds
     for h, line in pmonitor( popens, timeoutms=500 ):
         if h:
-            print '<%s>: %s' % ( h.name, line ),
+            info( '<%s>: %s' % ( h.name, line ) )
         if time() >= endTime:
             for p in popens.values():
                 p.send_signal( SIGINT )
     net.stop()
 
+
 if __name__ == '__main__':
+    setLogLevel( 'info' )
     pmonitorTest()

examples/scratchnet.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 Build a simple network from scratch, using mininet primitives.
@@ -8,13 +8,14 @@ but it exposes the configuration details and allows customization.
 For most tasks, the higher-level API will be preferable.
 """
 
+from time import sleep
+
 from mininet.net import Mininet
 from mininet.node import Node
 from mininet.link import Link
 from mininet.log import setLogLevel, info
 from mininet.util import quietRun
 
-from time import sleep
 
 def scratchNet( cname='controller', cargs='-v ptcp:' ):
     "Create network from scratch using Open vSwitch."
@@ -40,7 +41,7 @@ def scratchNet( cname='controller', cargs='-v ptcp:' ):
     switch.cmd( 'ovs-vsctl del-br dp0' )
     switch.cmd( 'ovs-vsctl add-br dp0' )
     for intf in switch.intfs.values():
-        print switch.cmd( 'ovs-vsctl add-port dp0 %s' % intf )
+        switch.cmd( 'ovs-vsctl add-port dp0 %s\n' % intf )
 
     # Note: controller and switch are in root namespace, and we
     # can connect via loopback interface
@@ -61,6 +62,7 @@ def scratchNet( cname='controller', cargs='-v ptcp:' ):
     switch.deleteIntfs()
     info( '\n' )
 
+
 if __name__ == '__main__':
     setLogLevel( 'info' )
     info( '*** Scratch network demo (kernel datapath)\n' )

examples/scratchnetuser.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 Build a simple network from scratch, using mininet primitives.
@@ -52,7 +52,7 @@ def scratchNetUser( cname='controller', cargs='ptcp:' ):
     info( '*** Starting controller and user datapath\n' )
     controller.cmd( cname + ' ' + cargs + '&' )
     switch.cmd( 'ifconfig lo 127.0.0.1' )
-    intfs = [ str( i ) for i in sintf1, sintf2 ]
+    intfs = str( sintf1 ), str( sintf2 )
     switch.cmd( 'ofdatapath -i ' + ','.join( intfs ) + ' ptcp: &' )
     switch.cmd( 'ofprotocol tcp:' + controller.IP() + ' tcp:localhost &' )
 
@@ -66,6 +66,7 @@ def scratchNetUser( cname='controller', cargs='ptcp:' ):
     switch.deleteIntfs()
     info( '\n' )
 
+
 if __name__ == '__main__':
     setLogLevel( 'info' )
     info( '*** Scratch network demo (user datapath)\n' )

examples/simpleperf.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 Simple example of setting network and CPU parameters
@@ -9,40 +9,53 @@ iperf will hang indefinitely if the TCP handshake fails
 to complete.
 """
 
+from sys import argv
+
 from mininet.topo import Topo
 from mininet.net import Mininet
 from mininet.node import CPULimitedHost
 from mininet.link import TCLink
 from mininet.util import dumpNodeConnections
-from mininet.log import setLogLevel
+from mininet.log import setLogLevel, info
 
-class SingleSwitchTopo(Topo):
+
+# It would be nice if we didn't have to do this:
+# pylint: disable=arguments-differ
+
+class SingleSwitchTopo( Topo ):
     "Single switch connected to n hosts."
-    def __init__(self, n=2, **opts):
-        Topo.__init__(self, **opts)
+    def build( self, n=2, lossy=True ):
         switch = self.addSwitch('s1')
         for h in range(n):
             # Each host gets 50%/n of system CPU
             host = self.addHost('h%s' % (h + 1),
                                 cpu=.5 / n)
-            # 10 Mbps, 5ms delay, 10% loss
-            self.addLink(host, switch,
-                         bw=10, delay='5ms', loss=10, use_htb=True)
+            if lossy:
+                # 10 Mbps, 5ms delay, 10% packet loss
+                self.addLink(host, switch,
+                             bw=10, delay='5ms', loss=10, use_htb=True)
+            else:
+                # 10 Mbps, 5ms delay, no packet loss
+                self.addLink(host, switch,
+                             bw=10, delay='5ms', loss=0, use_htb=True)
 
-def perfTest():
+
+def perfTest( lossy=True ):
     "Create network and run simple performance test"
-    topo = SingleSwitchTopo( n=4 )
+    topo = SingleSwitchTopo( n=4, lossy=lossy )
     net = Mininet( topo=topo,
-                  host=CPULimitedHost, link=TCLink,
-                  autoStaticArp=True )
+                   host=CPULimitedHost, link=TCLink,
+                   autoStaticArp=True )
     net.start()
-    print "Dumping host connections"
+    info( "Dumping host connections\n" )
     dumpNodeConnections(net.hosts)
-    print "Testing bandwidth between h1 and h4"
+    info( "Testing bandwidth between h1 and h4\n" )
     h1, h4 = net.getNodeByName('h1', 'h4')
-    results = net.iperf( ( h1, h4 ), l4Type='UDP' )
+    net.iperf( ( h1, h4 ), l4Type='UDP' )
     net.stop()
 
+
 if __name__ == '__main__':
-    setLogLevel('info')
-    perfTest()
+    setLogLevel( 'info' )
+    # Prevent test_simpleperf from failing due to packet loss
+    perfTest( lossy=( 'testmode' not in argv ) )

examples/sshd.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 Create a network and start sshd(8) on each host.
@@ -20,16 +20,16 @@ import sys
 
 from mininet.net import Mininet
 from mininet.cli import CLI
-from mininet.log import lg
+from mininet.log import lg, info
 from mininet.node import Node
 from mininet.topolib import TreeTopo
-from mininet.link import Link
 from mininet.util import waitListening
 
+
 def TreeNet( depth=1, fanout=2, **kwargs ):
     "Convenience function for creating tree networks."
     topo = TreeTopo( depth, fanout )
-    return Mininet( topo, **kwargs )
+    return Mininet( topo, waitConnected=True, **kwargs )
 
 def connectToRootNS( network, switch, ip, routes ):
     """Connect hosts to root namespace via switch. Starts network.
@@ -39,7 +39,7 @@ def connectToRootNS( network, switch, ip, routes ):
       routes: host networks to route to"""
     # Create a node in root namespace and link to switch 0
     root = Node( 'root', inNamespace=False )
-    intf = Link( root, switch ).intf1
+    intf = network.addLink( root, switch ).intf1
     root.setIP( ip, intf=intf )
     # Start network that now includes link to root namespace
     network.start()
@@ -47,6 +47,7 @@ def connectToRootNS( network, switch, ip, routes ):
     for route in routes:
         root.cmd( 'route add -net ' + route + ' dev ' + str( intf ) )
 
+# pylint: disable=too-many-arguments
 def sshd( network, cmd='/usr/sbin/sshd', opts='-D',
           ip='10.123.123.1/32', routes=None, switch=None ):
     """Start a network, connect it to root ns, and run sshd on all hosts.
@@ -60,27 +61,25 @@ def sshd( network, cmd='/usr/sbin/sshd', opts='-D',
     connectToRootNS( network, switch, ip, routes )
     for host in network.hosts:
         host.cmd( cmd + ' ' + opts + '&' )
-    print "*** Waiting for ssh daemons to start"
+    info( "*** Waiting for ssh daemons to start\n" )
     for server in network.hosts:
         waitListening( server=server, port=22, timeout=5 )
 
-    print
-    print "*** Hosts are running sshd at the following addresses:"
-    print
+    info( "\n*** Hosts are running sshd at the following addresses:\n" )
     for host in network.hosts:
-        print host.name, host.IP()
-    print
-    print "*** Type 'exit' or control-D to shut down network"
+        info( host.name, host.IP(), '\n' )
+    info( "\n*** Type 'exit' or control-D to shut down network\n" )
     CLI( network )
     for host in network.hosts:
         host.cmd( 'kill %' + cmd )
     network.stop()
 
+
 if __name__ == '__main__':
     lg.setLogLevel( 'info')
     net = TreeNet( depth=1, fanout=4 )
     # get sshd args from the command line or use default args
     # useDNS=no -u0 to avoid reverse DNS lookup timeout
-    opts = ' '.join( sys.argv[ 1: ] ) if len( sys.argv ) > 1 else (
+    argvopts = ' '.join( sys.argv[ 1: ] ) if len( sys.argv ) > 1 else (
         '-D -o UseDNS=no -u0' )
-    sshd( net, opts=opts )
+    sshd( net, opts=argvopts )

examples/test/runner.py

@@ -32,7 +32,8 @@ def runTests( testDir, verbosity=1 ):
     # discover all tests in testDir
     testSuite = unittest.defaultTestLoader.discover( testDir )
     # run tests
-    MininetTestRunner( verbosity=verbosity ).run( testSuite )
+    success = MininetTestRunner( verbosity=verbosity ).run( testSuite ).wasSuccessful()
+    sys.exit( 0 if success else 1 )
 
 if __name__ == '__main__':
     # get the directory containing example tests

examples/test/test_baresshd.py

@@ -5,8 +5,9 @@ Tests for baresshd.py
 """
 
 import unittest
-import pexpect
+from mininet.util import pexpect
 from mininet.clean import cleanup, sh
+from sys import stdout
 
 class testBareSSHD( unittest.TestCase ):
 
@@ -14,7 +15,9 @@ class testBareSSHD( unittest.TestCase ):
 
     def connected( self ):
         "Log into ssh server, check banner, then exit"
-        p = pexpect.spawn( 'ssh 10.0.0.1 -o StrictHostKeyChecking=no -i /tmp/ssh/test_rsa exit' )
+        p = pexpect.spawn( 'ssh 10.0.0.1 -o ConnectTimeout=1 '
+                           '-o StrictHostKeyChecking=no '
+                           '-i /tmp/ssh/test_rsa exit' )
         while True:
             index = p.expect( self.opts )
             if index == 0:
@@ -22,6 +25,7 @@ class testBareSSHD( unittest.TestCase ):
             else:
                 return False
 
+
     def setUp( self ):
         # verify that sshd is not running
         self.assertFalse( self.connected() )
@@ -36,7 +40,7 @@ class testBareSSHD( unittest.TestCase ):
                 '-o StrictModes=no' )
         p = pexpect.spawn( cmd )
         runOpts = [ 'You may now ssh into h1 at 10.0.0.1',
-                    'after 5 seconds, h1 is not listening on port 22', 
+                    'after 5 seconds, h1 is not listening on port 22',
                     pexpect.EOF, pexpect.TIMEOUT ]
         while True:
             index = p.expect( runOpts )
@@ -55,7 +59,7 @@ class testBareSSHD( unittest.TestCase ):
 
     def tearDown( self ):
         # kill the ssh process
-        sh( "ps aux | grep 'ssh.*Banner' | awk '{ print $2 }' | xargs kill" )
+        sh( "ps aux | grep ssh |grep Banner| awk '{ print $2 }' | xargs kill" )
         cleanup()
         # remove public key pair
         sh( 'rm -rf /tmp/ssh' )

examples/test/test_bind.py

@@ -5,7 +5,7 @@ Tests for bind.py
 """
 
 import unittest
-import pexpect
+from mininet.util import pexpect
 
 class testBind( unittest.TestCase ):
 

examples/test/test_clusterSanity.py

@@ -5,7 +5,7 @@ A simple sanity check test for cluster edition
 '''
 
 import unittest
-import pexpect
+from mininet.util import pexpect
 
 class clusterSanityCheck( unittest.TestCase ):
 
@@ -14,6 +14,8 @@ class clusterSanityCheck( unittest.TestCase ):
     def testClusterPingAll( self ):
         p = pexpect.spawn( 'python -m mininet.examples.clusterSanity' )
         p.expect( self.prompt )
+        p.sendline( 'py net.waitConnected()' )
+        p.expect( self.prompt )
         p.sendline( 'pingall' )
         p.expect ( '(\d+)% dropped' )
         percent = int( p.match.group( 1 ) ) if p.match else -1

examples/test/test_controllers.py

@@ -5,7 +5,7 @@ Tests for controllers.py and controllers2.py
 """
 
 import unittest
-import pexpect
+from mininet.util import pexpect
 
 class testControllers( unittest.TestCase ):
 

examples/test/test_controlnet.py

@@ -5,7 +5,9 @@ Test for controlnet.py
 """
 
 import unittest
-import pexpect
+from mininet.util import pexpect
+
+from sys import stdout
 
 class testControlNet( unittest.TestCase ):
 
@@ -13,7 +15,7 @@ class testControlNet( unittest.TestCase ):
 
     def testPingall( self ):
         "Simple pingall test that verifies 0% packet drop in data network"
-        p = pexpect.spawn( 'python -m mininet.examples.controlnet' )
+        p = pexpect.spawn( 'python -m mininet.examples.controlnet', logfile=stdout)
         p.expect( self.prompt )
         p.sendline( 'pingall' )
         p.expect ( '(\d+)% dropped' )
@@ -26,9 +28,9 @@ class testControlNet( unittest.TestCase ):
     def testFailover( self ):
         "Kill controllers and verify that switch, s1, fails over properly"
         count = 1
-        p = pexpect.spawn( 'python -m mininet.examples.controlnet' )
+        p = pexpect.spawn( 'python -m mininet.examples.controlnet', logfile=stdout )
         p.expect( self.prompt )
-        lp = pexpect.spawn( 'tail -f /tmp/s1-ofp.log' )
+        lp = pexpect.spawn( 'tail -f /tmp/s1-ofp.log', logfile=stdout )
         lp.expect( 'tcp:\d+\.\d+\.\d+\.(\d+):\d+: connected' )
         ip = int( lp.match.group( 1 ) )
         self.assertEqual( count, ip )

examples/test/test_cpu.py

@@ -5,18 +5,17 @@ Test for cpu.py
 
 results format:
 
-    sched   cpu client MB/s
-    
-    cfs 45.00%  13254.669841
-    cfs 40.00%  11822.441399
-    cfs 30.00%  5112.963009
-    cfs 20.00%  3449.090009
-    cfs 10.00%  2271.741564
+sched	cpu	received bits/sec
+cfs	50%	8.14e+09
+cfs	40%	6.48e+09
+cfs	30%	4.56e+09
+cfs	20%	2.84e+09
+cfs	10%	1.29e+09
 
 """
 
 import unittest
-import pexpect
+from mininet.util import pexpect
 import sys
 
 class testCPU( unittest.TestCase ):
@@ -26,21 +25,23 @@ class testCPU( unittest.TestCase ):
     @unittest.skipIf( '-quick' in sys.argv, 'long test' )
     def testCPU( self ):
         "Verify that CPU utilization is monotonically decreasing for each scheduler"
-        p = pexpect.spawn( 'python -m mininet.examples.cpu' )
+        p = pexpect.spawn( 'python -m mininet.examples.cpu', timeout=300 )
         # matches each line from results( shown above )
-        opts = [ '([a-z]+)\t([\d\.]+)%\t([\d\.]+)', 
+        opts = [ '([a-z]+)\t([\d\.]+)%\t([\d\.e\+]+)',
                  pexpect.EOF ]
         scheds = []
         while True:
-            index = p.expect( opts, timeout=600 )
+            index = p.expect( opts )
             if index == 0:
-                sched = p.match.group( 1 ) 
+                sched = p.match.group( 1 )
                 cpu = float( p.match.group( 2 ) )
                 bw = float( p.match.group( 3 ) )
                 if sched not in scheds:
                     scheds.append( sched )
                 else:
-                    self.assertTrue( bw < previous_bw )
+                    self.assertTrue( bw < previous_bw,
+                                     "%e should be less than %e\n" %
+                                     ( bw, previous_bw ) )
                 previous_bw = bw
             else:
                 break

examples/test/test_emptynet.py

@@ -5,7 +5,7 @@ Test for emptynet.py
 """
 
 import unittest
-import pexpect
+from mininet.util import pexpect
 
 class testEmptyNet( unittest.TestCase ):
 
@@ -19,7 +19,7 @@ class testEmptyNet( unittest.TestCase ):
         p.sendline( 'pingall' )
         p.expect ( '(\d+)% dropped' )
         percent = int( p.match.group( 1 ) ) if p.match else -1
-        self.assertEqual( percent, 0 ) 
+        self.assertEqual( percent, 0 )
         p.expect( self.prompt )
         # iperf test
         p.sendline( 'iperf' )

examples/test/test_hwintf.py

@@ -7,7 +7,7 @@ Test for hwintf.py
 import unittest
 import re
 
-import pexpect
+from mininet.util import pexpect
 
 from mininet.log import setLogLevel
 from mininet.node import Node
@@ -57,8 +57,8 @@ class testHwintf( unittest.TestCase ):
         p.wait()
 
     def tearDown( self ):
-        self.h3.terminate()
-        self.n0.terminate()
+        self.h3.stop( deleteIntfs=True )
+        self.n0.stop( deleteIntfs=True )
 
 if __name__ == '__main__':
     setLogLevel( 'warning' )

examples/test/test_intfOptions.py

@@ -1,42 +0,0 @@
-#!/usr/bin/env python
-
-"""
-Test for intfOptions.py
-"""
-
-import unittest
-import pexpect
-import sys
-
-class testIntfOptions( unittest.TestCase ):
-
-    def testIntfOptions( self ):
-        "verify that intf.config is correctly limiting traffic"
-        p = pexpect.spawn( 'python -m mininet.examples.intfOptions ' )
-        tolerance = .8
-        opts = [ "Results: \['([\d\.]+) .bits/sec",
-                 "Results: \['10M', '([\d\.]+) .bits/sec",
-                 "h(\d+)->h(\d+): (\d)/(\d), rtt min/avg/max/mdev ([\d\.]+)/([\d\.]+)/([\d\.]+)/([\d\.]+) ms",
-                 pexpect.EOF ]
-        while True:
-            index = p.expect( opts, timeout=600 )
-            if index == 0:
-                bw = float( p.match.group( 1 ) )
-                self.assertGreaterEqual( bw, float( 5 * tolerance ) )
-                self.assertLessEqual( bw, float( 5 + 5 * ( 1 - tolerance ) ) )
-            elif index == 1:
-                BW = 10
-                measuredBw = float( p.match.group( 1 ) )
-                loss = ( measuredBw / BW ) * 100
-                self.assertGreaterEqual( loss, 50 * tolerance )
-                self.assertLessEqual( loss,  50 + 50 * ( 1 - tolerance ) )
-            elif index == 2:
-                delay = float( p.match.group( 6 ) )
-                self.assertGreaterEqual( delay, 15 * tolerance )
-                self.assertLessEqual( delay,  15 + 15 * ( 1 - tolerance ) )
-            else:
-                break
-
-
-if __name__ == '__main__':
-    unittest.main()

examples/test/test_intfoptions.py

@@ -0,0 +1,46 @@
+#!/usr/bin/env python
+
+"""
+Test for intfOptions.py
+"""
+
+import unittest
+from mininet.util import pexpect
+import sys
+
+class testIntfOptions( unittest.TestCase ):
+
+    def testIntfOptions( self ):
+        "verify that intf.config is correctly limiting traffic"
+        p = pexpect.spawn( 'python -m mininet.examples.intfoptions ' )
+        tolerance = .25  # plus or minus 25% for cloud CI tests
+        opts = [ "Results: \['([\d\.]+) .bits/sec",
+                 "Results: \['10M', '([\d\.]+) .bits/sec",
+                 "h(\d+)->h(\d+): (\d)/(\d),"
+                 "rtt min/avg/max/mdev ([\d\.]+)/([\d\.]+)/([\d\.]+)/([\d\.]+) ms",
+                 pexpect.EOF ]
+        while True:
+            index = p.expect( opts, timeout=600 )
+            if index == 0:
+                BW = 10
+                bw = float( p.match.group( 1 ) )
+                self.assertGreaterEqual( bw, BW * ( 1 - tolerance ) )
+                self.assertLessEqual( bw, BW * ( 1 + tolerance ) )
+            elif index == 1:
+                BW = 10
+                measuredBw = float( p.match.group( 1 ) )
+                loss = ( measuredBw / BW ) * 100
+                self.assertGreaterEqual( loss, 50 * ( 1 - tolerance ),
+                                         'loss of %d%% << 50%%' % loss )
+                self.assertLessEqual( loss,  50 * ( 1 + tolerance ),
+                                      'loss of %d%% >> 50%%' % loss  )
+            elif index == 2:
+                delay = float( p.match.group( 6 ) )
+                self.assertGreaterEqual( delay, 15 * ( 1 - tolerance ) )
+                self.assertLessEqual( delay,  15 * ( 1 + tolerance ) )
+            else:
+                break
+
+
+if __name__ == '__main__':
+    unittest.main()

examples/test/test_limit.py

@@ -5,7 +5,7 @@ Test for limit.py
 """
 
 import unittest
-import pexpect
+from mininet.util import pexpect
 import sys
 
 class testLimit( unittest.TestCase ):
@@ -14,8 +14,8 @@ class testLimit( unittest.TestCase ):
     def testLimit( self ):
         "Verify that CPU limits are within a 2% tolerance of limit for each scheduler"
         p = pexpect.spawn( 'python -m mininet.examples.limit' )
-        opts = [ '\*\*\* Testing network ([\d\.]+) Mbps', 
-                 '\*\*\* Results: \[([\d\., ]+)\]', 
+        opts = [ '\*\*\* Testing network ([\d\.]+) Mbps',
+                 '\*\*\* Results: \[([\d\., ]+)\]',
                  pexpect.EOF ]
         count = 0
         bw = 0

examples/test/test_linearbandwidth.py

@@ -5,7 +5,7 @@ Test for linearbandwidth.py
 """
 
 import unittest
-import pexpect
+from mininet.util import pexpect
 import sys
 
 class testLinearBandwidth( unittest.TestCase ):
@@ -15,8 +15,8 @@ class testLinearBandwidth( unittest.TestCase ):
         "Verify that bandwidth is monotonically decreasing as # of hops increases"
         p = pexpect.spawn( 'python -m mininet.examples.linearbandwidth' )
         count = 0
-        opts = [ '\*\*\* Linear network results', 
-                 '(\d+)\s+([\d\.]+) (.bits)', 
+        opts = [ '\*\*\* Linear network results',
+                 '(\d+)\s+([\d\.]+) (.bits)',
                  pexpect.EOF ]
         while True:
             index = p.expect( opts, timeout=600 )
@@ -34,8 +34,8 @@ class testLinearBandwidth( unittest.TestCase ):
                     bw *= 10 ** 9
                 # check that we have a previous result to compare to
                 if n != 1:
-                    info = ( 'bw: %d bits/s across %d switches, '
-                             'previous: %d bits/s across %d switches' %
+                    info = ( 'bw: %.2e bits/s across %d switches, '
+                             'previous: %.2e bits/s across %d switches' %
                              ( bw, n, previous_bw, previous_n ) )
                     self.assertTrue( bw < previous_bw, info )
                 previous_bw, previous_n = bw, n

examples/test/test_linuxrouter.py

@@ -5,7 +5,7 @@ Test for linuxrouter.py
 """
 
 import unittest
-import pexpect
+from mininet.util import pexpect
 from mininet.util import quietRun
 
 class testLinuxRouter( unittest.TestCase ):

examples/test/test_multilink.py

@@ -0,0 +1,55 @@
+#!/usr/bin/env python
+
+'''
+Test for multiple links between nodes
+validates mininet interfaces against systems interfaces
+'''
+
+import unittest
+from mininet.util import pexpect
+
+class testMultiLink( unittest.TestCase ):
+
+    prompt = 'mininet>'
+
+    def testMultiLink(self):
+        p = pexpect.spawn( 'python -m mininet.examples.multilink' )
+        p.expect( self.prompt )
+        p.sendline( 'intfs' )
+        p.expect( 's(\d): lo' )
+        intfsOutput = p.before
+        # parse interfaces from mininet intfs, and store them in a list
+        hostToIntfs = intfsOutput.split( '\r\n' )[ 1:3 ]
+        intfList = []
+        for hostToIntf in hostToIntfs:
+            intfList += [ intf for intf in
+                          hostToIntf.split()[1].split(',') ]
+
+        # get interfaces from system by running ifconfig on every host
+        sysIntfList = []
+        opts = [ 'h(\d)-eth(\d)', self.prompt ]
+        p.expect( self.prompt )
+
+        p.sendline( 'h1 ifconfig' )
+        while True:
+            p.expect( opts )
+            if p.after == self.prompt:
+                break
+            sysIntfList.append( p.after )
+
+        p.sendline( 'h2 ifconfig' )
+        while True:
+            p.expect( opts )
+            if p.after == self.prompt:
+                break
+            sysIntfList.append( p.after )
+
+        failMsg = ( 'The systems interfaces and mininet interfaces\n'
+                    'are not the same' )
+
+        self.assertEqual( sysIntfList, intfList, msg=failMsg )
+        p.sendline( 'exit' )
+        p.wait()
+
+if __name__ == '__main__':
+        unittest.main()

examples/test/test_multiping.py

@@ -5,13 +5,13 @@ Test for multiping.py
 """
 
 import unittest
-import pexpect
+from mininet.util import pexpect
 from collections import defaultdict
 
 class testMultiPing( unittest.TestCase ):
 
     def testMultiPing( self ):
-        """Verify that each target is pinged at least once, and 
+        """Verify that each target is pinged at least once, and
            that pings to 'real' targets are successful and unknown targets fail"""
         p = pexpect.spawn( 'python -m mininet.examples.multiping' )
         opts = [ "Host (h\d+) \(([\d.]+)\) will be pinging ips: ([\d\. ]+)",
@@ -31,18 +31,20 @@ class testMultiPing( unittest.TestCase ):
                 target = p.match.group(3)
                 received = int( p.match.group(4) )
                 if target == '10.0.0.200':
-                    self.assertEqual( received, 0 )
+                    self.assertEqual( received, 0, p.match.group(0) + '\n' +
+                                      target + ' received %d != 0 packets' % received )
                 else:
-                    self.assertEqual( received, 1 )
+                    self.assertEqual( received, 1, p.match.group(0) + '\n' +
+                                      target + ' received %d != 1 packets' % received )
                 try:
                     pings[ name ].remove( target )
                 except:
                     pass
             else:
                 break
-        self.assertTrue( len( pings ) > 0 )
+        self.assertTrue( len( pings ) > 0, 'too few pings' )
         for t in pings.values():
-            self.assertEqual( len( t ), 0 )
+            self.assertEqual( len( t ), 0, 'missed ping target(s): %s' % t )
 
 if __name__ == '__main__':
     unittest.main()

examples/test/test_multipoll.py

@@ -5,7 +5,7 @@ Test for multipoll.py
 """
 
 import unittest
-import pexpect
+from mininet.util import pexpect
 
 class testMultiPoll( unittest.TestCase ):
 
@@ -16,7 +16,7 @@ class testMultiPoll( unittest.TestCase ):
                  "(h\d+): \d+ bytes from",
                  "Monitoring output for (\d+) seconds",
                  pexpect.EOF ]
-        pings = {}
+        pings, seconds = {}, -1
         while True:
             index = p.expect( opts )
             if index == 0:
@@ -32,7 +32,8 @@ class testMultiPoll( unittest.TestCase ):
         self.assertTrue( len( pings ) > 0 )
         # make sure we have received at least one ping per second
         for count in pings.values():
-            self.assertTrue( count >= seconds )
+            self.assertTrue( count >= seconds,
+                             '%d pings < %d seconds' % ( count, seconds ) )
 
 if __name__ == '__main__':
     unittest.main()

examples/test/test_multitest.py

@@ -5,7 +5,7 @@ Test for multitest.py
 """
 
 import unittest
-import pexpect
+from mininet.util import pexpect
 
 class testMultiTest( unittest.TestCase ):
 

examples/test/test_nat.py

@@ -5,7 +5,7 @@ Test for nat.py
 """
 
 import unittest
-import pexpect
+from mininet.util import pexpect
 from mininet.util import quietRun
 
 destIP = '8.8.8.8' # Google DNS
@@ -14,7 +14,7 @@ class testNAT( unittest.TestCase ):
 
     prompt = 'mininet>'
 
-    @unittest.skipIf( '0 received' in quietRun( 'ping -c 1 %s' % destIP ), 
+    @unittest.skipIf( '0 received' in quietRun( 'ping -c 1 %s' % destIP ),
                       'Destination IP is not reachable' )
     def testNAT( self ):
         "Attempt to ping an IP on the Internet and verify 0% packet loss"

examples/test/test_natnet.py

@@ -5,7 +5,7 @@ Test for natnet.py
 """
 
 import unittest
-import pexpect
+from mininet.util import pexpect
 from mininet.util import quietRun
 
 class testNATNet( unittest.TestCase ):

examples/test/test_numberedports.py

@@ -5,7 +5,7 @@ Test for numberedports.py
 """
 
 import unittest
-import pexpect
+from mininet.util import pexpect
 from collections import defaultdict
 from mininet.node import OVSSwitch
 
@@ -15,8 +15,8 @@ class testNumberedports( unittest.TestCase ):
     def testConsistency( self ):
         """verify consistency between mininet and ovs ports"""
         p = pexpect.spawn( 'python -m mininet.examples.numberedports' )
-        opts = [ 'Validating that s1-eth\d is actually on port \d ... Validated.', 
-                 'Validating that s1-eth\d is actually on port \d ... WARNING', 
+        opts = [ 'Validating that s1-eth\d is actually on port \d ... Validated.',
+                 'Validating that s1-eth\d is actually on port \d ... WARNING',
                  pexpect.EOF ]
         correct_ports = True
         count = 0
@@ -34,7 +34,7 @@ class testNumberedports( unittest.TestCase ):
     def testNumbering( self ):
         """verify that all of the port numbers are printed correctly and consistent with their interface"""
         p = pexpect.spawn( 'python -m mininet.examples.numberedports' )
-        opts = [ 's1-eth(\d+) :  (\d+)', 
+        opts = [ 's1-eth(\d+) :  (\d+)',
                  pexpect.EOF ]
         count_intfs = 0
         while True:

examples/test/test_popen.py

@@ -5,7 +5,7 @@ Test for popen.py and popenpoll.py
 """
 
 import unittest
-import pexpect
+from mininet.util import pexpect
 
 class testPopen( unittest.TestCase ):
 

examples/test/test_scratchnet.py

@@ -5,7 +5,7 @@ Test for scratchnet.py
 """
 
 import unittest
-import pexpect
+from mininet.util import pexpect
 
 class testScratchNet( unittest.TestCase ):
 
@@ -14,8 +14,9 @@ class testScratchNet( unittest.TestCase ):
     def pingTest( self, name ):
         "Verify that no ping packets were dropped"
         p = pexpect.spawn( 'python -m %s' % name )
-        index = p.expect( self.opts )
+        index = p.expect( self.opts, timeout=120 )
         self.assertEqual( index, 0 )
+        p.wait()
 
     def testPingKernel( self ):
         self.pingTest( 'mininet.examples.scratchnet' )

examples/test/test_simpleperf.py

@@ -5,7 +5,7 @@ Test for simpleperf.py
 """
 
 import unittest
-import pexpect
+from mininet.util import pexpect
 import sys
 from mininet.log import setLogLevel
 
@@ -16,15 +16,15 @@ class testSimplePerf( unittest.TestCase ):
     @unittest.skipIf( '-quick' in sys.argv, 'long test' )
     def testE2E( self ):
         "Run the example and verify iperf results"
+        # 10 Mb/s, plus or minus 20% tolerance
         BW = 10
-        TOLERANCE = .8
-        expectedBw = BW * TOLERANCE
-        p = pexpect.spawn( 'python -m mininet.examples.simpleperf' )
+        TOLERANCE = .2
+        p = pexpect.spawn( 'python -m mininet.examples.simpleperf testmode' )
         # check iperf results
         p.expect( "Results: \['10M', '([\d\.]+) .bits/sec", timeout=480 )
         measuredBw = float( p.match.group( 1 ) )
-        lowerBound = expectedBw * TOLERANCE
-        upperBound = expectedBw + expectedBw * ( 1 - TOLERANCE )
+        lowerBound = BW * ( 1 - TOLERANCE )
+        upperBound = BW + ( 1 + TOLERANCE )
         self.assertGreaterEqual( measuredBw, lowerBound )
         self.assertLessEqual( measuredBw, upperBound )
         p.wait()

examples/test/test_sshd.py

@@ -5,7 +5,7 @@ Test for sshd.py
 """
 
 import unittest
-import pexpect
+from mininet.util import pexpect
 from mininet.clean import sh
 
 class testSSHD( unittest.TestCase ):
@@ -14,19 +14,20 @@ class testSSHD( unittest.TestCase ):
 
     def connected( self, ip ):
         "Log into ssh server, check banner, then exit"
-        # Note: this test will fail if "Welcome" is not in the sshd banner 
+        # Note: this test will fail if "Welcome" is not in the sshd banner
         # and '#'' or '$'' are not in the prompt
-        p = pexpect.spawn( 'ssh -i /tmp/ssh/test_rsa %s' % ip, timeout=10 )
+        ssh = 'ssh -o StrictHostKeyChecking=no -i /tmp/ssh/test_rsa ' + ip
+        p = pexpect.spawn( ssh, timeout=5 )
         while True:
             index = p.expect( self.opts )
             if index == 0:
-                print p.match.group(0)
+                print( p.match.group(0) )
                 p.sendline( 'yes' )
             elif index == 1:
                 return False
             elif index == 2:
                 p.sendline( 'exit' )
-                p.wait()    
+                p.wait()
                 return True
             else:
                 return False
@@ -57,4 +58,3 @@ class testSSHD( unittest.TestCase ):
 
 if __name__ == '__main__':
     unittest.main()
-

examples/test/test_tree1024.py

@@ -5,7 +5,7 @@ Test for tree1024.py
 """
 
 import unittest
-import pexpect
+from mininet.util import pexpect
 import sys
 
 class testTree1024( unittest.TestCase ):
@@ -17,13 +17,15 @@ class testTree1024( unittest.TestCase ):
         "Run the example and do a simple ping test from h1 to h1024"
         p = pexpect.spawn( 'python -m mininet.examples.tree1024' )
         p.expect( self.prompt, timeout=6000 ) # it takes awhile to set up
-        p.sendline( 'h1 ping -c 1 h1024' )
+        p.sendline( 'h1 ping -c 20 h1024' )
         p.expect ( '(\d+)% packet loss' )
-        percent = int( p.match.group( 1 ) ) if p.match else -1
+        packetLossPercent = int( p.match.group( 1 ) ) if p.match else -1
         p.expect( self.prompt )
         p.sendline( 'exit' )
         p.wait()
-        self.assertEqual( percent, 0 )
+        # Tolerate slow startup on some systems - we should revisit this
+        # and determine the root cause.
+        self.assertLess( packetLossPercent, 60 )
 
 if __name__ == '__main__':
     unittest.main()

examples/test/test_treeping64.py

@@ -5,7 +5,7 @@ Test for treeping64.py
 """
 
 import unittest
-import pexpect
+from mininet.util import pexpect
 import sys
 
 class testTreePing64( unittest.TestCase ):

examples/test/test_vlanhost.py

@@ -5,7 +5,7 @@ Test for vlanhost.py
 """
 
 import unittest
-import pexpect
+from mininet.util import pexpect
 import sys
 from mininet.util import quietRun
 
@@ -47,4 +47,4 @@ class testVLANHost( unittest.TestCase ):
         self.assertEqual( i, 0 ) # check vlan intf is present
 
 if __name__ == '__main__':
-    unittest.main()
+    unittest.main()

examples/tree1024.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 Create a 1024-host network, and run the CLI on it.
@@ -9,10 +9,12 @@ and running sysctl -p. Check util/sysctl_addon.
 
 from mininet.cli import CLI
 from mininet.log import setLogLevel
-from mininet.node import OVSKernelSwitch
+from mininet.node import OVSSwitch
 from mininet.topolib import TreeNet
+from mininet.examples.treeping64 import HostV4
 
 if __name__ == '__main__':
     setLogLevel( 'info' )
-    network = TreeNet( depth=2, fanout=32, switch=OVSKernelSwitch )
+    network = TreeNet( depth=2, fanout=32, host=HostV4,
+                       switch=OVSSwitch, waitConnected=True)
     network.run( CLI, network )

examples/treeping64.py

@@ -1,31 +1,42 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 "Create a 64-node tree network, and test connectivity using ping."
 
-from mininet.log import setLogLevel
-from mininet.node import UserSwitch, OVSKernelSwitch  # , KernelSwitch
+
+from mininet.log import setLogLevel, info
+from mininet.node import UserSwitch, OVSKernelSwitch, Host
 from mininet.topolib import TreeNet
 
+
+class HostV4( Host ):
+    "Try to IPv6 and its awful neighbor discovery"
+    def __init__( self, *args, **kwargs ):
+        super( HostV4, self ).__init__( *args, **kwargs )
+        cfgs = [ 'all.disable_ipv6=1', 'default.disable_ipv6=1',
+                 'default.autoconf=0', 'lo.autoconf=0' ]
+        for cfg in cfgs:
+            self.cmd( 'sysctl -w net.ipv6.conf.' + cfg )
+
+
 def treePing64():
     "Run ping test on 64-node tree networks."
 
     results = {}
-    switches = {  # 'reference kernel': KernelSwitch,
-                  'reference user': UserSwitch,
-                  'Open vSwitch kernel': OVSKernelSwitch }
+    switches = { 'reference user': UserSwitch,
+                 'Open vSwitch kernel': OVSKernelSwitch }
 
-    for name in switches:
-        print "*** Testing", name, "datapath"
-        switch = switches[ name ]
-        network = TreeNet( depth=2, fanout=8, switch=switch )
+    for name, switch in switches.items():
+        info( "*** Testing", name, "datapath\n" )
+        network = TreeNet( depth=2, fanout=8, switch=switch,
+                           waitConnected=True )
         result = network.run( network.pingAll )
         results[ name ] = result
 
-    print
-    print "*** Tree network ping results:"
+    info( "\n*** Tree network ping results:\n" )
     for name in switches:
-        print "%s: %d%% packet loss" % ( name, results[ name ] )
-    print
+        info( "%s: %d%% packet loss\n" % ( name, results[ name ] ) )
+    info( '\n' )
+
 
 if __name__ == '__main__':
     setLogLevel( 'info' )

examples/vlanhost.py

@@ -24,23 +24,28 @@ Usage (example uses VLAN ID=1000):
 
 """
 
+from sys import exit  # pylint: disable=redefined-builtin
+
 from mininet.node import Host
 from mininet.topo import Topo
 from mininet.util import quietRun
 from mininet.log import error
 
-class VLANHost( Host ):
 
-   def config( self, vlan=100, **params ):
+class VLANHost( Host ):
+    "Host connected to VLAN interface"
+
+    # pylint: disable=arguments-differ
+    def config( self, vlan=100, **params ):
         """Configure VLANHost according to (optional) parameters:
            vlan: VLAN ID for default interface"""
 
-        r = super( Host, self ).config( **params )
+        r = super( VLANHost, self ).config( **params )
 
         intf = self.defaultIntf()
         # remove IP from default, "physical" interface
         self.cmd( 'ifconfig %s inet 0' % intf )
-        # create VLAN interface 
+        # create VLAN interface
         self.cmd( 'vconfig add %s %d' % ( intf, vlan ) )
         # assign the host's IP to the VLAN interface
         self.cmd( 'ifconfig %s.%d inet %s' % ( intf, vlan, params['ip'] ) )
@@ -53,6 +58,7 @@ class VLANHost( Host ):
 
         return r
 
+
 hosts = { 'vlan': VLANHost }
 
 
@@ -64,11 +70,13 @@ def exampleAllHosts( vlan ):
 
     # Start a basic network using our VLANHost
     topo = SingleSwitchTopo( k=2 )
-    net = Mininet( host=host, topo=topo )
+    net = Mininet( host=host, topo=topo, waitConnected=True )
     net.start()
     CLI( net )
     net.stop()
 
+# pylint: disable=arguments-differ
+
 class VLANStarTopo( Topo ):
     """Example topology that uses host in multiple VLANs
 
@@ -90,14 +98,15 @@ class VLANStarTopo( Topo ):
             self.addLink( h, s1 )
 
 
-def exampleCustomTags( vlan ):
+def exampleCustomTags():
     """Simple example that exercises VLANStarTopo"""
 
-    net = Mininet( topo=VLANStarTopo() )
+    net = Mininet( topo=VLANStarTopo(), waitConnected=True )
     net.start()
     CLI( net )
     net.stop()
 
+
 if __name__ == '__main__':
     import sys
     from functools import partial
@@ -110,16 +119,12 @@ if __name__ == '__main__':
     setLogLevel( 'info' )
 
     if not quietRun( 'which vconfig' ):
-        error( "Cannot find command 'vconfig'\nThe packge",
+        error( "Cannot find command 'vconfig'\nThe package",
                "'vlan' is required in Ubuntu or Debian,",
                "or 'vconfig' in Fedora\n" )
         exit()
-    try:
-        vlan = int( sys.argv[ 1 ] )
-    except Exception:
-        vlan = None
 
-    if vlan:
-        exampleAllHosts( vlan )
+    if len( sys.argv ) >= 2:
+        exampleAllHosts( vlan=int( sys.argv[ 1 ] ) )
     else:
-        exampleCustomTags( vlan )
+        exampleCustomTags()

mininet/__main__.py

@@ -0,0 +1 @@
+../bin/mn

mininet/clean.py

@@ -10,16 +10,21 @@ It may also get rid of 'false positives', but hopefully
 nothing irreplaceable!
 """
 
-from subprocess import Popen, PIPE, check_output as co
+from subprocess import ( Popen, PIPE, check_output as co,
+                         CalledProcessError )
 import time
 
 from mininet.log import info
 from mininet.term import cleanUpScreens
+from mininet.util import decode
 
 def sh( cmd ):
     "Print a command and send it to the shell"
     info( cmd + '\n' )
-    return Popen( [ '/bin/sh', '-c', cmd ], stdout=PIPE ).communicate()[ 0 ]
+    p = Popen(  # pylint: disable=consider-using-with
+        [ '/bin/sh', '-c', cmd ], stdout=PIPE )
+    result = p.communicate()[ 0 ]
+    return decode( result )
 
 def killprocs( pattern ):
     "Reliably terminate processes matching a pattern (including args)"
@@ -27,69 +32,98 @@ def killprocs( pattern ):
     # Make sure they are gone
     while True:
         try:
-            pids = co( 'pgrep -f %s' % pattern )
-        except:
+            pids = co( [ 'pgrep', '-f', pattern ] )
+        except CalledProcessError:
             pids = ''
         if pids:
-            sh( 'pkill -f 9 mininet:' )
-            sleep( .5 )
+            sh( 'pkill -9 -f %s' % pattern )
+            time.sleep( .5 )
         else:
             break
 
-def cleanup():
-    """Clean up junk which might be left over from old runs;
-       do fast stuff before slow dp and link removal!"""
+class Cleanup( object ):
+    "Wrapper for cleanup()"
 
-    info("*** Removing excess controllers/ofprotocols/ofdatapaths/pings/noxes"
-         "\n")
-    zombies = 'controller ofprotocol ofdatapath ping nox_core lt-nox_core '
-    zombies += 'ovs-openflowd ovs-controller udpbwtest mnexec ivs'
-    # Note: real zombie processes can't actually be killed, since they
-    # are already (un)dead. Then again,
-    # you can't connect to them either, so they're mostly harmless.
-    # Send SIGTERM first to give processes a chance to shutdown cleanly.
-    sh( 'killall ' + zombies + ' 2> /dev/null' )
-    time.sleep(1)
-    sh( 'killall -9 ' + zombies + ' 2> /dev/null' )
+    callbacks = []
 
-    # And kill off sudo mnexec
-    sh( 'pkill -9 -f "sudo mnexec"')
+    @classmethod
+    def cleanup( cls):
+        """Clean up junk which might be left over from old runs;
+           do fast stuff before slow dp and link removal!"""
 
-    info( "*** Removing junk from /tmp\n" )
-    sh( 'rm -f /tmp/vconn* /tmp/vlogs* /tmp/*.out /tmp/*.log' )
+        info( "*** Removing excess controllers/ofprotocols/ofdatapaths/"
+              "pings/noxes\n" )
+        zombies = ( 'controller ofprotocol ofdatapath ping nox_core '
+                    'lt-nox_core ovs-openflowd ovs-controller '
+                    'ovs-testcontroller udpbwtest mnexec ivs ryu-manager ' )
+        # Note: real zombie processes can't actually be killed, since they
+        # are already (un)dead. Then again,
+        # you can't connect to them either, so they're mostly harmless.
+        # Send SIGTERM first to give processes a chance to shutdown cleanly.
+        sh( 'killall ' + zombies + ' 2> /dev/null' )
+        time.sleep( 1 )
+        sh( 'killall -9 ' + zombies + ' 2> /dev/null' )
 
-    info( "*** Removing old X11 tunnels\n" )
-    cleanUpScreens()
+        # And kill off sudo mnexec
+        sh( 'pkill -9 -f "sudo mnexec"')
 
-    info( "*** Removing excess kernel datapaths\n" )
-    dps = sh( "ps ax | egrep -o 'dp[0-9]+' | sed 's/dp/nl:/'" ).splitlines()
-    for dp in dps:
-        if dp:
-            sh( 'dpctl deldp ' + dp )
+        info( "*** Removing junk from /tmp\n" )
+        sh( 'rm -f /tmp/vconn* /tmp/vlogs* /tmp/*.out /tmp/*.log' )
 
-    info( "***  Removing OVS datapaths" )
-    dps = sh("ovs-vsctl --timeout=1 list-br").strip().splitlines()
-    if dps:
-        sh( "ovs-vsctl " + " -- ".join( "--if-exists del-br " + dp
-                                       for dp in dps if dp ) )
-    # And in case the above didn't work...
-    dps = sh("ovs-vsctl --timeout=1 list-br").strip().splitlines()
-    for dp in dps:
-        sh( 'ovs-vsctl del-br ' + dp )
+        info( "*** Removing old X11 tunnels\n" )
+        cleanUpScreens()
 
-    info( "*** Removing all links of the pattern foo-ethX\n" )
-    links = sh( "ip link show | "
-                "egrep -o '([-_.[:alnum:]]+-eth[[:digit:]]+)'" ).splitlines()
-    for link in links:
-        if link:
-            sh( "ip link del " + link )
+        info( "*** Removing excess kernel datapaths\n" )
+        dps = sh( "ps ax | egrep -o 'dp[0-9]+' | sed 's/dp/nl:/'"
+                  ).splitlines()
+        for dp in dps:
+            if dp:
+                sh( 'dpctl deldp ' + dp )
+        info( "***  Removing OVS datapaths\n" )
+        dps = sh("ovs-vsctl --timeout=1 list-br").strip().splitlines()
+        if dps:
+            sh( "ovs-vsctl " + " -- ".join( "--if-exists del-br " + dp
+                                            for dp in dps if dp ) )
+        # And in case the above didn't work...
+        dps = sh( "ovs-vsctl --timeout=1 list-br" ).strip().splitlines()
+        for dp in dps:
+            sh( 'ovs-vsctl del-br ' + dp )
 
-    info( "*** Killing stale mininet node processes\n" )
-    killprocs( 'mininet:' )
+        info( "*** Removing all links of the pattern foo-ethX\n" )
+        links = sh( "ip link show | "
+                    "egrep -o '([-_.[:alnum:]]+-eth[[:digit:]]+)'"
+                    ).splitlines()
+        # Delete blocks of links
+        n = 1000  # chunk size
+        for i in range( 0, len( links ), n ):
+            cmd = ';'.join( 'ip link del %s' % link
+                             for link in links[ i : i + n ] )
+            sh( '( %s ) 2> /dev/null' % cmd )
 
-    info ( "*** Shutting down stale tunnels\n" )
-    killprocs( 'Tunnel=Ethernet' )
-    killprocs( '.ssh/mn')
-    sh( 'rm -f ~/.ssh/mn/*' )
-    
-    info( "*** Cleanup complete.\n" )
+        if 'tap9' in sh( 'ip link show' ):
+            info( "*** Removing tap9 - assuming it's from cluster edition\n" )
+            sh( 'ip link del tap9' )
+
+        info( "*** Killing stale mininet node processes\n" )
+        killprocs( 'mininet:' )
+
+        info( "*** Shutting down stale tunnels\n" )
+        killprocs( 'Tunnel=Ethernet' )
+        killprocs( '.ssh/mn')
+        sh( 'rm -f ~/.ssh/mn/*' )
+
+        # Call any additional cleanup code if necessary
+        for callback in cls.callbacks:
+            callback()
+
+        info( "*** Cleanup complete.\n" )
+
+    @classmethod
+    def addCleanupCallback( cls, callback ):
+        "Add cleanup callback"
+        if callback not in cls.callbacks:
+            cls.callbacks.append( callback )
+
+
+cleanup = Cleanup.cleanup
+addCleanupCallback = Cleanup.addCleanupCallback

mininet/cli.py

@@ -29,6 +29,8 @@ from subprocess import call
 from cmd import Cmd
 from os import isatty
 from select import poll, POLLIN
+import select
+import errno
 import sys
 import time
 import os
@@ -36,53 +38,89 @@ import atexit
 
 from mininet.log import info, output, error
 from mininet.term import makeTerms, runX11
-from mininet.util import ( quietRun, isShellBuiltin, dumpNodeConnections,
-                         dumpPorts )
+from mininet.util import ( quietRun, dumpNodeConnections,
+                           dumpPorts )
 
 class CLI( Cmd ):
     "Simple command-line interface to talk to nodes."
 
     prompt = 'mininet> '
 
-    def __init__( self, mininet, stdin=sys.stdin, script=None ):
+    def __init__( self, mininet, stdin=sys.stdin, script=None,
+                  **kwargs ):
+        """Start and run interactive or batch mode CLI
+           mininet: Mininet network object
+           stdin: standard input for CLI
+           script: script to run in batch mode"""
         self.mn = mininet
         # Local variable bindings for py command
         self.locals = { 'net': mininet }
         # Attempt to handle input
-        self.stdin = stdin
         self.inPoller = poll()
         self.inPoller.register( stdin )
         self.inputFile = script
-        Cmd.__init__( self )
+        Cmd.__init__( self, stdin=stdin, **kwargs )
         info( '*** Starting CLI:\n' )
 
-        # Set up history if readline is available
-        try:
-            import readline
-        except ImportError:
-            pass
-        else:
-            history_path = os.path.expanduser('~/.mininet_history')
-            if os.path.isfile(history_path):
-                readline.read_history_file(history_path)
-            atexit.register(lambda: readline.write_history_file(history_path))
-
         if self.inputFile:
             self.do_source( self.inputFile )
             return
+
+        self.initReadline()
+        self.run()
+
+    readlineInited = False
+
+    @classmethod
+    def initReadline( cls ):
+        "Set up history if readline is available"
+        # Only set up readline once to prevent multiplying the history file
+        if cls.readlineInited:
+            return
+        cls.readlineInited = True
+        try:
+            # pylint: disable=import-outside-toplevel
+            from readline import ( read_history_file, write_history_file,
+                                   set_history_length )
+        except ImportError:
+            pass
+        else:
+            history_path = os.path.expanduser( '~/.mininet_history' )
+            if os.path.isfile( history_path ):
+                read_history_file( history_path )
+                set_history_length( 1000 )
+
+            def writeHistory():
+                "Write out history file"
+                try:
+                    write_history_file( history_path )
+                except IOError:
+                    # Ignore probably spurious IOError
+                    pass
+            atexit.register( writeHistory )
+
+    def run( self ):
+        "Run our cmdloop(), catching KeyboardInterrupt"
         while True:
             try:
                 # Make sure no nodes are still waiting
                 for node in self.mn.values():
                     while node.waiting:
+                        info( 'stopping', node, '\n' )
                         node.sendInt()
                         node.waitOutput()
                 if self.isatty():
-                    quietRun( 'stty echo sane intr "^C"' )
+                    quietRun( 'stty echo sane intr ^C' )
                 self.cmdloop()
                 break
             except KeyboardInterrupt:
-                output( '\nInterrupt\n' )
+                # Output a message - unless it's also interrupted
+                # pylint: disable=broad-except
+                try:
+                    output( '\nInterrupt\n' )
+                except Exception:
+                    pass
+                # pylint: enable=broad-except
 
     def emptyline( self ):
         "Don't repeat last command when you hit return."
@@ -93,11 +131,6 @@ class CLI( Cmd ):
         self.locals.update( self.mn )
         return self.locals
 
-    # Disable pylint "Unused argument: 'arg's'" messages, as well as
-    # "method could be a function" warning, since each CLI function
-    # must have the same interface
-    # pylint: disable-msg=R0201
-
     helpStr = (
         'You may also send a command to a node using:\n'
         '  <node> command {args}\n'
@@ -117,10 +150,10 @@ class CLI( Cmd ):
         '  mininet> xterm h2\n\n'
     )
 
-    def do_help( self, line ):
+    def do_help( self, line ):  # pylint: disable=arguments-renamed
         "Describe available CLI commands."
         Cmd.do_help( self, line )
-        if line is '':
+        if line == '':
             output( self.helpStr )
 
     def do_nodes( self, _line ):
@@ -128,7 +161,7 @@ class CLI( Cmd ):
         nodes = ' '.join( sorted( self.mn ) )
         output( 'available nodes are: \n%s\n' % nodes )
 
-    def do_ports( self, line ):
+    def do_ports( self, _line ):
         "display ports and interfaces for each switch"
         dumpPorts( self.mn.switches )
 
@@ -139,37 +172,39 @@ class CLI( Cmd ):
     def do_sh( self, line ):
         """Run an external shell command
            Usage: sh [cmd args]"""
+        assert self  # satisfy pylint and allow override
         call( line, shell=True )
 
     # do_py() and do_px() need to catch any exception during eval()/exec()
-    # pylint: disable-msg=W0703
+    # pylint: disable=broad-except
 
     def do_py( self, line ):
         """Evaluate a Python expression.
            Node names may be used, e.g.: py h1.cmd('ls')"""
         try:
+            # pylint: disable=eval-used
             result = eval( line, globals(), self.getLocals() )
-            if not result:
+            if result is None:
                 return
             elif isinstance( result, str ):
                 output( result + '\n' )
             else:
                 output( repr( result ) + '\n' )
-        except Exception, e:
+        except Exception as e:
             output( str( e ) + '\n' )
 
     # We are in fact using the exec() pseudo-function
-    # pylint: disable-msg=W0122
+    # pylint: disable=exec-used
 
     def do_px( self, line ):
         """Execute a Python statement.
             Node names may be used, e.g.: px print h1.cmd('ls')"""
         try:
             exec( line, globals(), self.getLocals() )
-        except Exception, e:
+        except Exception as e:
             output( str( e ) + '\n' )
 
-    # pylint: enable-msg=W0703,W0122
+    # pylint: enable=broad-except,exec-used
 
     def do_pingall( self, line ):
         "Ping between all hosts."
@@ -284,6 +319,7 @@ class CLI( Cmd ):
 
     def do_exit( self, _line ):
         "Exit"
+        assert self  # satisfy pylint and allow override
         return 'exited by user command'
 
     def do_quit( self, line ):
@@ -316,13 +352,13 @@ class CLI( Cmd ):
             error( 'usage: source <file>\n' )
             return
         try:
-            self.inputFile = open( args[ 0 ] )
-            while True:
-                line = self.inputFile.readline()
-                if len( line ) > 0:
-                    self.onecmd( line )
-                else:
-                    break
+            with open( args[ 0 ] ) as self.inputFile:
+                while True:
+                    line = self.inputFile.readline()
+                    if len( line ) > 0:
+                        self.onecmd( line )
+                    else:
+                        break
         except IOError:
             error( 'error reading file %s\n' % args[ 0 ] )
         self.inputFile.close()
@@ -346,22 +382,49 @@ class CLI( Cmd ):
         elapsed = time.time() - start
         self.stdout.write("*** Elapsed time: %0.6f secs\n" % elapsed)
 
-    def do_links( self, line ):
+    def do_links( self, _line ):
         "Report on links"
         for link in self.mn.links:
-            print link, link.status()
+            output( link, link.status(), '\n' )
+
+    def do_switch( self, line ):
+        "Starts or stops a switch"
+        args = line.split()
+        if len(args) != 2:
+            error( 'invalid number of args: switch <switch name>'
+                   '{start, stop}\n' )
+            return
+        sw = args[ 0 ]
+        command = args[ 1 ]
+        if sw not in self.mn or self.mn.get( sw ) not in self.mn.switches:
+            error( 'invalid switch: %s\n' % args[ 1 ] )
+        else:
+            sw = args[ 0 ]
+            command = args[ 1 ]
+            if command == 'start':
+                self.mn.get( sw ).start( self.mn.controllers )
+            elif command == 'stop':
+                self.mn.get( sw ).stop( deleteIntfs=False )
+            else:
+                error( 'invalid command: '
+                       'switch <switch name> {start, stop}\n' )
+
+    def do_wait( self, _line ):
+        "Wait until all switches have connected to a controller"
+        self.mn.waitConnected()
 
     def default( self, line ):
         """Called on an input line when the command prefix is not recognized.
-        Overridden to run shell commands when a node is the first CLI argument.
-        Past the first CLI argument, node names are automatically replaced with
-        corresponding IP addrs."""
+           Overridden to run shell commands when a node is the first
+           CLI argument.  Past the first CLI argument, node names are
+           automatically replaced with corresponding IP addrs."""
 
         first, args, line = self.parseline( line )
 
         if first in self.mn:
             if not args:
-                print "*** Enter a command for node: %s <cmd>" % first
+                error( '*** Please enter a command for node: %s <cmd>\n'
+                       % first )
                 return
             node = self.mn[ first ]
             rest = args.split( ' ' )
@@ -377,8 +440,6 @@ class CLI( Cmd ):
         else:
             error( '*** Unknown command: %s\n' % line )
 
-    # pylint: enable-msg=R0201
-
     def waitForNode( self, node ):
         "Wait for a node to finish, and print its output."
         # Pollers
@@ -395,12 +456,14 @@ class CLI( Cmd ):
             try:
                 bothPoller.poll()
                 # XXX BL: this doesn't quite do what we want.
+                # pylint: disable=condition-evals-to-constant
                 if False and self.inputFile:
                     key = self.inputFile.read( 1 )
-                    if key is not '':
+                    if key != '':
                         node.write( key )
                     else:
                         self.inputFile = None
+                # pylint: enable=condition-evals-to-constant
                 if isReadable( self.inPoller ):
                     key = self.stdin.read( 1 )
                     node.write( key )
@@ -414,6 +477,13 @@ class CLI( Cmd ):
                 # it's possible to interrupt ourselves after we've
                 # read data but before it has been printed.
                 node.sendInt()
+            except select.error as e:
+                # pylint: disable=unpacking-non-sequence
+                # pylint: disable=unbalanced-tuple-unpacking
+                errno_, errmsg = e.args
+                if errno_ != errno.EINTR:
+                    error( "select.error: %s, %s" % (errno_, errmsg) )
+                    node.sendInt()
 
     def precmd( self, line ):
         "allow for comments in the cli"
@@ -430,3 +500,4 @@ def isReadable( poller ):
         mask = fdmask[ 1 ]
         if mask & POLLIN:
             return True
+        return False

mininet/link.py

@@ -24,16 +24,21 @@ TCIntf: interface with bandwidth limiting and delay via tc
 Link: basic link class for creating veth pairs
 """
 
-from mininet.log import info, error, debug
-from mininet.util import makeIntfPair, quietRun
 import re
 
+from mininet.log import info, error, debug
+from mininet.util import makeIntfPair
+
+# Make pylint happy:
+# pylint: disable=too-many-arguments
+
+
 class Intf( object ):
 
     "Basic interface object that can configure itself."
 
     def __init__( self, name, node=None, port=None, link=None,
-                  mac=None, srcNode=None, **params ):
+                  mac=None, **params ):
         """name: interface name (e.g. h1-eth0)
            node: owning node (where this intf most likely lives)
            link: parent link if we're part of a link
@@ -43,13 +48,19 @@ class Intf( object ):
         self.link = link
         self.mac = mac
         self.ip, self.prefixLen = None, None
-        
+
         # if interface is lo, we know the ip is 127.0.0.1.
         # This saves an ifconfig command per node
         if self.name == 'lo':
             self.ip = '127.0.0.1'
+            self.prefixLen = 8
         # Add to node (and move ourselves if necessary )
-        node.addIntf( self, port=port )
+        if node:
+            moveIntfFn = params.pop( 'moveIntfFn', None )
+            if moveIntfFn:
+                node.addIntf( self, port=port, moveIntfFn=moveIntfFn )
+            else:
+                node.addIntf( self, port=port )
         # Save params for future reference
         self.params = params
         self.config( **params )
@@ -70,6 +81,9 @@ class Intf( object ):
             self.ip, self.prefixLen = ipstr.split( '/' )
             return self.ifconfig( ipstr, 'up' )
         else:
+            if prefixLen is None:
+                raise Exception( 'No prefix length set for IP address %s'
+                                 % ( ipstr, ) )
             self.ip, self.prefixLen = ipstr, prefixLen
             return self.ifconfig( '%s/%s' % ( ipstr, prefixLen ) )
 
@@ -88,7 +102,8 @@ class Intf( object ):
         "Return updated IP address based on ifconfig"
         # use pexec instead of node.cmd so that we dont read
         # backgrounded output from the cli.
-        ifconfig, _err, _exitCode = self.node.pexec( 'ifconfig %s' % self.name )
+        ifconfig, _err, _exitCode = self.node.pexec(
+            'ifconfig %s' % self.name )
         ips = self._ipMatchRegex.findall( ifconfig )
         self.ip = ips[ 0 ] if ips else None
         return self.ip
@@ -136,6 +151,9 @@ class Intf( object ):
 
     def rename( self, newname ):
         "Rename interface"
+        if self.node and self.name in self.node.nameToIntf:
+            # rename intf in node's nameToIntf
+            self.node.nameToIntf[newname] = self.node.nameToIntf.pop(self.name)
         self.ifconfig( 'down' )
         result = self.cmd( 'ip link set', self.name, 'name', newname )
         self.name = newname
@@ -154,13 +172,13 @@ class Intf( object ):
            method: config method name
            param: arg=value (ignore if value=None)
            value may also be list or dict"""
-        name, value = param.items()[ 0 ]
+        name, value = list( param.items() )[ 0 ]
         f = getattr( self, method, None )
         if not f or value is None:
-            return
-        if type( value ) is list:
+            return None
+        if isinstance( value, list ):
             result = f( *value )
-        elif type( value ) is dict:
+        elif isinstance( value, dict ):
             result = f( **value )
         else:
             result = f( value )
@@ -188,13 +206,16 @@ class Intf( object ):
     def delete( self ):
         "Delete interface"
         self.cmd( 'ip link del ' + self.name )
-        if self.node.inNamespace:
-            # Link may have been dumped into root NS
-            quietRun( 'ip link del ' + self.name )
+        # We used to do this, but it slows us down:
+        # if self.node.inNamespace:
+        # Link may have been dumped into root NS
+        # quietRun( 'ip link del ' + self.name )
+        self.node.delIntf( self )
+        self.link = None
 
     def status( self ):
         "Return intf status as a string"
-        links, err_, result_ = self.node.pexec( 'ip link show' )
+        links, _err, _result = self.node.pexec( 'ip link show' )
         if self.name in links:
             return "OK"
         else:
@@ -212,15 +233,19 @@ class TCIntf( Intf ):
        Allows specification of bandwidth limits (various methods)
        as well as delay, loss and max queue length"""
 
+    # The parameters we use seem to work reasonably up to 1 Gb/sec
+    # For higher data rates, we will probably need to change them.
+    bwParamMax = 1000
+
     def bwCmds( self, bw=None, speedup=0, use_hfsc=False, use_tbf=False,
                 latency_ms=None, enable_ecn=False, enable_red=False ):
         "Return tc commands to set bandwidth"
 
         cmds, parent = [], ' root '
 
-        if bw and ( bw < 0 or bw > 1000 ):
-            error( 'Bandwidth', bw, 'is outside range 0..1000 Mbps\n' )
-
+        if bw and ( bw < 0 or bw > self.bwParamMax ):
+            error( 'Bandwidth limit', bw, 'is outside supported range 0..%d'
+                   % self.bwParamMax, '- ignoring\n' )
         elif bw is not None:
             # BL: this seems a bit brittle...
             if ( speedup > 0 and
@@ -236,7 +261,7 @@ class TCIntf( Intf ):
                           + 'rate %fMbit ul rate %fMbit' % ( bw, bw ) ]
             elif use_tbf:
                 if latency_ms is None:
-                    latency_ms = 15 * 8 / bw
+                    latency_ms = 15.0 * 8 / bw
                 cmds += [ '%s qdisc add dev %s root handle 5: tbf ' +
                           'rate %fMbit burst 15000 latency %fms' %
                           ( bw, latency_ms ) ]
@@ -268,18 +293,14 @@ class TCIntf( Intf ):
                    loss=None, max_queue_size=None ):
         "Internal method: return tc commands for delay and loss"
         cmds = []
-        if delay and delay < 0:
-            error( 'Negative delay', delay, '\n' )
-        elif jitter and jitter < 0:
-            error( 'Negative jitter', jitter, '\n' )
-        elif loss and ( loss < 0 or loss > 100 ):
+        if loss and ( loss < 0 or loss > 100 ):
             error( 'Bad loss percentage', loss, '%%\n' )
         else:
             # Delay/jitter/loss/max queue size
             netemargs = '%s%s%s%s' % (
                 'delay %s ' % delay if delay is not None else '',
                 '%s ' % jitter if jitter is not None else '',
-                'loss %d ' % loss if loss is not None else '',
+                'loss %.5f ' % loss if (loss is not None and loss > 0) else '',
                 'limit %d' % max_queue_size if max_queue_size is not None
                 else '' )
             if netemargs:
@@ -295,27 +316,53 @@ class TCIntf( Intf ):
         debug(" *** executing command: %s\n" % c)
         return self.cmd( c )
 
-    def config( self, bw=None, delay=None, jitter=None, loss=None,
-                disable_gro=True, speedup=0, use_hfsc=False, use_tbf=False,
+    def config(  # pylint: disable=arguments-renamed,arguments-differ
+                self,
+                bw=None, delay=None, jitter=None, loss=None,
+                gro=False, txo=True, rxo=True,
+                speedup=0, use_hfsc=False, use_tbf=False,
                 latency_ms=None, enable_ecn=False, enable_red=False,
                 max_queue_size=None, **params ):
-        "Configure the port and set its properties."
+        """Configure the port and set its properties.
+           bw: bandwidth in b/s (e.g. '10m')
+           delay: transmit delay (e.g. '1ms' )
+           jitter: jitter (e.g. '1ms')
+           loss: loss (e.g. '1%' )
+           gro: enable GRO (False)
+           txo: enable transmit checksum offload (True)
+           rxo: enable receive checksum offload (True)
+           speedup: experimental switch-side bw option
+           use_hfsc: use HFSC scheduling
+           use_tbf: use TBF scheduling
+           latency_ms: TBF latency parameter
+           enable_ecn: enable ECN (False)
+           enable_red: enable RED (False)
+           max_queue_size: queue limit parameter for netem"""
+
+        # Support old names for parameters
+        gro = not params.pop( 'disable_gro', not gro )
 
         result = Intf.config( self, **params)
 
-        # Disable GRO
-        if disable_gro:
-            self.cmd( 'ethtool -K %s gro off' % self )
+        def on( isOn ):
+            "Helper method: bool -> 'on'/'off'"
+            return 'on' if isOn else 'off'
+
+        # Set offload parameters with ethool
+        self.cmd( 'ethtool -K', self,
+                  'gro', on( gro ),
+                  'tx', on( txo ),
+                  'rx', on( rxo ) )
 
         # Optimization: return if nothing else to configure
         # Question: what happens if we want to reset things?
         if ( bw is None and not delay and not loss
              and max_queue_size is None ):
-            return
+            return None
 
         # Clear existing configuration
         tcoutput = self.tc( '%s qdisc show dev %s' )
-        if "priomap" not in tcoutput:
+        if "priomap" not in tcoutput and "noqueue" not in tcoutput:
             cmds = [ '%s qdisc del dev %s root' ]
         else:
             cmds = []
@@ -330,15 +377,16 @@ class TCIntf( Intf ):
 
         # Delay/jitter/loss/max_queue_size using netem
         delaycmds, parent = self.delayCmds( delay=delay, jitter=jitter,
-                                loss=loss, max_queue_size=max_queue_size,
-                                parent=parent )
+                                            loss=loss,
+                                            max_queue_size=max_queue_size,
+                                            parent=parent )
         cmds += delaycmds
 
         # Ugly but functional: display configuration info
         stuff = ( ( [ '%.2fMbit' % bw ] if bw is not None else [] ) +
                   ( [ '%s delay' % delay ] if delay is not None else [] ) +
                   ( [ '%s jitter' % jitter ] if jitter is not None else [] ) +
-                  ( ['%d%% loss' % loss ] if loss is not None else [] ) +
+                  ( ['%.5f%% loss' % loss ] if loss is not None else [] ) +
                   ( [ 'ECN' ] if enable_ecn else [ 'RED' ]
                     if enable_red else [] ) )
         info( '(' + ' '.join( stuff ) + ') ' )
@@ -362,10 +410,11 @@ class Link( object ):
     """A basic link is just a veth pair.
        Other types of links could be tunnels, link emulators, etc.."""
 
+    # pylint: disable=too-many-branches
     def __init__( self, node1, node2, port1=None, port2=None,
                   intfName1=None, intfName2=None, addr1=None, addr2=None,
                   intf=Intf, cls1=None, cls2=None, params1=None,
-                  params2=None ):
+                  params2=None, fast=True, **params ):
         """Create veth link to another node, making two new interfaces.
            node1: first node
            node2: second node
@@ -375,18 +424,15 @@ class Link( object ):
            cls1, cls2: optional interface-specific constructors
            intfName1: node1 interface name (optional)
            intfName2: node2  interface name (optional)
-           params1: parameters for interface 1
-           params2: parameters for interface 2"""
+           params1: parameters for interface 1 (optional)
+           params2: parameters for interface 2 (optional)
+           **params: additional parameters for both interfaces"""
+
         # This is a bit awkward; it seems that having everything in
         # params is more orthogonal, but being able to specify
         # in-line arguments is more convenient! So we support both.
-        if params1 is None:
-            params1 = {}
-        if params2 is None:
-            params2 = {}
-        # Allow passing in params1=params2
-        if params2 is params1:
-            params2 = dict( params1 )
+        params1 = dict( params1 ) if params1 else {}
+        params2 = dict( params2 ) if params2 else {}
         if port1 is not None:
             params1[ 'port' ] = port1
         if port2 is not None:
@@ -400,7 +446,18 @@ class Link( object ):
         if not intfName2:
             intfName2 = self.intfName( node2, params2[ 'port' ] )
 
-        self.makeIntfPair( intfName1, intfName2, addr1, addr2 )
+        # Update with remaining parameter list
+        params1.update( params )
+        params2.update( params )
+
+        self.fast = fast
+        if fast:
+            params1.setdefault( 'moveIntfFn', self._ignore )
+            params2.setdefault( 'moveIntfFn', self._ignore )
+            self.makeIntfPair( intfName1, intfName2, addr1, addr2,
+                               node1, node2, deleteIntfs=False )
+        else:
+            self.makeIntfPair( intfName1, intfName2, addr1, addr2 )
 
         if not cls1:
             cls1 = intf
@@ -415,27 +472,46 @@ class Link( object ):
         # All we are is dust in the wind, and our two interfaces
         self.intf1, self.intf2 = intf1, intf2
 
-    def intfName( _self, node, n ):
+    # pylint: enable=too-many-branches
+
+    @staticmethod
+    def _ignore( *args, **kwargs ):
+        "Ignore any arguments"
+        pass
+
+    def intfName( self, node, n ):
         "Construct a canonical interface name node-ethN for interface n."
+        # Leave this as an instance method for now
+        assert self
         return node.name + '-eth' + repr( n )
 
     @classmethod
-    def makeIntfPair( _cls, intfname1, intfname2, addr1=None, addr2=None ):
+    def makeIntfPair( cls, intfname1, intfname2, addr1=None, addr2=None,
+                      node1=None, node2=None, deleteIntfs=True ):
         """Create pair of interfaces
-           intfname1: name of interface 1
-           intfname2: name of interface 2
+           intfname1: name for interface 1
+           intfname2: name for interface 2
+           addr1: MAC address for interface 1 (optional)
+           addr2: MAC address for interface 2 (optional)
+           node1: home node for interface 1 (optional)
+           node2: home node for interface 2 (optional)
            (override this method [and possibly delete()]
            to change link type)"""
-        return makeIntfPair( intfname1, intfname2, addr1, addr2 )
+        # Leave this as a class method for now
+        assert cls
+        return makeIntfPair( intfname1, intfname2, addr1, addr2, node1, node2,
+                             deleteIntfs=deleteIntfs )
 
     def delete( self ):
         "Delete this link"
         self.intf1.delete()
+        self.intf1 = None
         self.intf2.delete()
+        self.intf2 = None
 
     def stop( self ):
         "Override to stop and clean up link as needed"
-        pass
+        self.delete()
 
     def status( self ):
         "Return link status as a string"
@@ -444,15 +520,63 @@ class Link( object ):
     def __str__( self ):
         return '%s<->%s' % ( self.intf1, self.intf2 )
 
+
+class OVSIntf( Intf ):
+    "Patch interface on an OVSSwitch"
+
+    def ifconfig( self, *args ):
+        cmd = ' '.join( args )
+        if cmd == 'up':
+            # OVSIntf is always up
+            return
+        else:
+            raise Exception( 'OVSIntf cannot do ifconfig ' + cmd )
+
+
+class OVSLink( Link ):
+    """Link that makes patch links between OVSSwitches
+       Warning: in testing we have found that no more
+       than ~64 OVS patch links should be used in row."""
+
+    def __init__( self, node1, node2, **kwargs ):
+        "See Link.__init__() for options"
+        if 'OVSSwitch' not in globals():
+            # pylint: disable=import-outside-toplevel,cyclic-import
+            from mininet.node import OVSSwitch
+        self.isPatchLink = False
+        if ( isinstance( node1, OVSSwitch ) and
+             isinstance( node2, OVSSwitch ) ):
+            self.isPatchLink = True
+            kwargs.update( cls1=OVSIntf, cls2=OVSIntf )
+        Link.__init__( self, node1, node2, **kwargs )
+
+    # pylint: disable=arguments-renamed, arguments-differ, signature-differs
+    def makeIntfPair( self, *args, **kwargs ):
+        "Usually delegated to OVSSwitch"
+        if self.isPatchLink:
+            return None, None
+        else:
+            return Link.makeIntfPair( *args, **kwargs )
+
+
 class TCLink( Link ):
-    "Link with symmetric TC interfaces configured via opts"
-    def __init__( self, node1, node2, port1=None, port2=None,
-                  intfName1=None, intfName2=None,
-                  addr1=None, addr2=None, **params ):
-        Link.__init__( self, node1, node2, port1=port1, port2=port2,
-                       intfName1=intfName1, intfName2=intfName2,
-                       cls1=TCIntf,
-                       cls2=TCIntf,
-                       addr1=addr1, addr2=addr2,
-                       params1=params,
-                       params2=params )
+    "Link with TC interfaces"
+    def __init__( self, *args, **kwargs):
+        kwargs.setdefault( 'cls1', TCIntf )
+        kwargs.setdefault( 'cls2', TCIntf )
+        Link.__init__( self, *args, **kwargs)
+
+
+class TCULink( TCLink ):
+    """TCLink with default settings optimized for UserSwitch
+       (txo=rxo=0/False).  Unfortunately with recent Linux kernels,
+       enabling TX and RX checksum offload on veth pairs doesn't work
+       well with UserSwitch: either it gets terrible performance or
+       TCP packets with bad checksums are generated, forwarded, and
+       *dropped* due to having bad checksums! OVS and LinuxBridge seem
+       to cope with this somehow, but it is likely to be an issue with
+       many software Ethernet bridges."""
+
+    def __init__( self, *args, **kwargs ):
+        kwargs.update( txo=False, rxo=False )
+        TCLink.__init__( self, *args, **kwargs )

mininet/log.py

@@ -4,6 +4,7 @@ import logging
 from logging import Logger
 import types
 
+
 # Create a new loglevel, 'CLI info', which enables a Mininet user to see only
 # the output of the commands they execute, plus any errors or warnings.  This
 # level is in between info and warning.  CLI info-level commands should not be
@@ -14,13 +15,14 @@ LEVELS = { 'debug': logging.DEBUG,
            'info': logging.INFO,
            'output': OUTPUT,
            'warning': logging.WARNING,
+           'warn': logging.WARNING,
            'error': logging.ERROR,
            'critical': logging.CRITICAL }
 
 # change this to logging.INFO to get printouts when running unit tests
 LOGLEVELDEFAULT = OUTPUT
 
-#default: '%(asctime)s - %(name)s - %(levelname)s - %(message)s'
+# default: '%(asctime)s - %(name)s - %(levelname)s - %(message)s'
 LOGMSGFORMAT = '%(message)s'
 
 
@@ -51,7 +53,7 @@ class StreamHandlerNoNewline( logging.StreamHandler ):
             self.flush()
         except ( KeyboardInterrupt, SystemExit ):
             raise
-        except:
+        except:  # noqa pylint: disable=bare-except
             self.handleError( record )
 
 
@@ -95,9 +97,9 @@ class MininetLogger( Logger, object ):
 
     __metaclass__ = Singleton
 
-    def __init__( self ):
+    def __init__( self, name="mininet" ):
 
-        Logger.__init__( self, "mininet" )
+        Logger.__init__( self, name )
 
         # create console handler
         ch = StreamHandlerNoNewline()
@@ -105,30 +107,22 @@ class MininetLogger( Logger, object ):
         formatter = logging.Formatter( LOGMSGFORMAT )
         # add formatter to ch
         ch.setFormatter( formatter )
-        # add ch to lg
+        # add ch to lg and initialize log level
         self.addHandler( ch )
-
+        self.ch = ch
         self.setLogLevel()
 
     def setLogLevel( self, levelname=None ):
         """Setup loglevel.
            Convenience function to support lowercase names.
            levelName: level name from LEVELS"""
-        level = LOGLEVELDEFAULT
-        if levelname is not None:
-            if levelname not in LEVELS:
-                raise Exception( 'unknown levelname seen in setLogLevel' )
-            else:
-                level = LEVELS.get( levelname, level )
-
+        if levelname and levelname not in LEVELS:
+            print(LEVELS)
+            raise Exception( 'setLogLevel: unknown levelname %s' % levelname )
+        level = LEVELS.get( levelname, LOGLEVELDEFAULT  )
         self.setLevel( level )
-        self.handlers[ 0 ].setLevel( level )
+        self.ch.setLevel( level )
 
-    # pylint: disable-msg=E0202
-    # "An attribute inherited from mininet.log hide this method"
-    # Not sure why this is occurring - this function definitely gets called.
-
-    # See /usr/lib/python2.5/logging/__init__.py; modified from warning()
     def output( self, msg, *args, **kwargs ):
         """Log 'msg % args' with severity 'OUTPUT'.
 
@@ -137,14 +131,11 @@ class MininetLogger( Logger, object ):
 
            logger.warning("Houston, we have a %s", "cli output", exc_info=1)
         """
-        if self.manager.disable >= OUTPUT:
+        if getattr( self.manager, 'disabled', 0 ) >= OUTPUT:
             return
         if self.isEnabledFor( OUTPUT ):
             self._log( OUTPUT, msg, args, kwargs )
 
-    # pylint: enable-msg=E0202
-
-lg = MininetLogger()
 
 # Make things a bit more convenient by adding aliases
 # (info, warn, error, debug) and allowing info( 'this', 'is', 'OK' )
@@ -160,7 +151,7 @@ def makeListCompatible( fn ):
         "Generated function. Closure-ish."
         if len( args ) == 1:
             return fn( *args )
-        args = ' '.join( [ str( arg ) for arg in args ] )
+        args = ' '.join( str( arg ) for arg in args )
         return fn( args )
 
     # Fix newfn's name and docstring
@@ -168,9 +159,14 @@ def makeListCompatible( fn ):
     setattr( newfn, '__doc__', fn.__doc__ )
     return newfn
 
-info, output, warn, error, debug = (
-    lg.info, lg.output, lg.warn, lg.error, lg.debug ) = [
-        makeListCompatible( f ) for f in
-            lg.info, lg.output, lg.warn, lg.error, lg.debug ]
 
+# Initialize logger and logging functions
+
+logging.setLoggerClass( MininetLogger )
+lg = logging.getLogger( "mininet" )
+_loggers = lg.info, lg.output, lg.warning, lg.error, lg.debug
+_loggers = tuple( makeListCompatible( logger ) for logger in _loggers )
+lg.info, lg.output, lg.warning, lg.error, lg.debug = _loggers
+info, output, warning, error, debug = _loggers
+warn = warning  # alternate/old name
 setLogLevel = lg.setLogLevel

mininet/moduledeps.py

@@ -1,8 +1,11 @@
 "Module dependency utility functions for Mininet."
 
-from mininet.util import quietRun
-from mininet.log import info, error, debug
 from os import environ
+from sys import exit  # pylint: disable=redefined-builtin
+
+from mininet.util import quietRun, BaseString
+from mininet.log import info, error, debug
+
 
 def lsmod():
     "Return output of lsmod."
@@ -18,6 +21,7 @@ def modprobe( mod ):
        mod: module string"""
     return quietRun( [ 'modprobe', mod ] )
 
+
 OF_KMOD = 'ofdatapath'
 OVS_KMOD = 'openvswitch_mod'  # Renamed 'openvswitch' in OVS 1.7+/Linux 3.5+
 TUN = 'tun'
@@ -28,9 +32,9 @@ def moduleDeps( subtract=None, add=None ):
        add: string or list of module names to add, if not already loaded"""
     subtract = subtract if subtract is not None else []
     add = add if add is not None else []
-    if type( subtract ) is str:
+    if isinstance( subtract, BaseString ):
         subtract = [ subtract ]
-    if type( add ) is str:
+    if isinstance( add, BaseString ):
         add = [ add ]
     for mod in subtract:
         if mod in lsmod():

mininet/net.py

@@ -91,26 +91,30 @@ import re
 import select
 import signal
 import random
-import copy
+
+from sys import exit  # pylint: disable=redefined-builtin
 from time import sleep
 from itertools import chain, groupby
 from math import ceil
 
 from mininet.cli import CLI
-from mininet.log import info, error, debug, output, warn
-from mininet.node import Host, OVSKernelSwitch, DefaultController, Controller
+from mininet.log import info, error, output, warn
+from mininet.node import ( Node, Host, OVSKernelSwitch, DefaultController,
+                           Controller )
 from mininet.nodelib import NAT
 from mininet.link import Link, Intf
-from mininet.util import quietRun, fixLimits, numCores, ensureRoot
-from mininet.util import macColonHex, ipStr, ipParse, netParse, ipAdd
+from mininet.util import ( quietRun, fixLimits, numCores, ensureRoot,
+                           macColonHex, ipStr, ipParse, netParse, ipAdd,
+                           waitListening, BaseString, fmtBps )
 from mininet.term import cleanUpScreens, makeTerms
 
 # Mininet version: should be consistent with README and LICENSE
-VERSION = "2.1.0+"
+VERSION = "2.3.1b3"
 
 class Mininet( object ):
     "Network emulation with hosts spawned in network namespaces."
 
+    # pylint: disable=too-many-arguments
     def __init__( self, topo=None, switch=OVSKernelSwitch, host=Host,
                   controller=DefaultController, link=Link, intf=Intf,
                   build=True, xterms=False, cleanup=False, ipBase='10.0.0.0/8',
@@ -133,7 +137,9 @@ class Mininet( object ):
            autoStaticArp: set all-pairs static MAC addrs?
            autoPinCpus: pin hosts to (real) cores (requires CPULimitedHost)?
            listenPort: base listening port to open; will be incremented for
-               each additional switch in the net if inNamespace=False"""
+               each additional switch in the net if inNamespace=False
+           waitConnected: wait for switches to Connect?
+               (False; True/None=wait indefinitely; time(s)=timed wait)"""
         self.topo = topo
         self.switch = switch
         self.host = host
@@ -142,7 +148,9 @@ class Mininet( object ):
         self.intf = intf
         self.ipBase = ipBase
         self.ipBaseNum, self.prefixLen = netParse( self.ipBase )
-        self.nextIP = 1  # start for address allocation
+        hostIP = ( 0xffffffff >> self.prefixLen ) & self.ipBaseNum
+        # Start for address allocation
+        self.nextIP = hostIP if hostIP > 0 else 1
         self.inNamespace = inNamespace
         self.xterms = xterms
         self.cleanup = cleanup
@@ -169,16 +177,17 @@ class Mininet( object ):
         if topo and build:
             self.build()
 
-
     def waitConnected( self, timeout=None, delay=.5 ):
-        """wait for each switch to connect to a controller,
-           up to 5 seconds
-           timeout: time to wait, or None to wait indefinitely
+        """wait for each switch to connect to a controller
+           timeout: time to wait, or None or True to wait indefinitely
            delay: seconds to sleep per iteration
            returns: True if all switches are connected"""
         info( '*** Waiting for switches to connect\n' )
-        time = 0
+        time = 0.0
         remaining = list( self.switches )
+        # False: 0s timeout; None: wait forever (preserve 2.2 behavior)
+        if isinstance( timeout, bool ):
+            timeout = None if timeout else 0
         while True:
             for switch in tuple( remaining ):
                 if switch.connected():
@@ -187,12 +196,12 @@ class Mininet( object ):
             if not remaining:
                 info( '\n' )
                 return True
-            if time > timeout and timeout is not None:
+            if timeout is not None and time >= timeout:
                 break
             sleep( delay )
             time += delay
         warn( 'Timed out after %d seconds\n' % time )
-        for switch in remaining:
+        for switch in remaining.copy():
             if not switch.connected():
                 warn( 'Warning: %s is not connected to a controller\n'
                       % switch.name )
@@ -225,6 +234,24 @@ class Mininet( object ):
         self.nameToNode[ name ] = h
         return h
 
+    def delNode( self, node, nodes=None):
+        """Delete node
+           node: node to delete
+           nodes: optional list to delete from (e.g. self.hosts)"""
+        if nodes is None:
+            nodes = ( self.hosts if node in self.hosts else
+                      ( self.switches if node in self.switches else
+                        ( self.controllers if node in self.controllers else
+                          [] ) ) )
+        node.stop( deleteIntfs=True )
+        node.terminate()
+        nodes.remove( node )
+        del self.nameToNode[ node.name ]
+
+    def delHost( self, host ):
+        "Delete a host"
+        self.delNode( host, nodes=self.hosts )
+
     def addSwitch( self, name, cls=None, **params ):
         """Add switch.
            name: name of switch to add
@@ -243,6 +270,10 @@ class Mininet( object ):
         self.nameToNode[ name ] = sw
         return sw
 
+    def delSwitch( self, switch ):
+        "Delete a switch"
+        self.delNode( switch, nodes=self.switches )
+
     def addController( self, name='c0', controller=None, **params ):
         """Add controller.
            controller: Controller class"""
@@ -253,25 +284,41 @@ class Mininet( object ):
         if isinstance( name, Controller ):
             controller_new = name
             # Pylint thinks controller is a str()
-            # pylint: disable=E1103
+            # pylint: disable=maybe-no-member
             name = controller_new.name
-            # pylint: enable=E1103
+            # pylint: enable=maybe-no-member
         else:
             controller_new = controller( name, **params )
         # Add new controller to net
-        if controller_new: # allow controller-less setups
+        if controller_new:  # allow controller-less setups
             self.controllers.append( controller_new )
             self.nameToNode[ name ] = controller_new
         return controller_new
 
-    def addNAT( self, name='nat0', connect=True, inNamespace=False, **params ):
-        nat = self.addHost( name, cls=NAT, inNamespace=inNamespace, 
+    def delController( self, controller ):
+        """Delete a controller
+           Warning - does not reconfigure switches, so they
+           may still attempt to connect to it!"""
+        self.delNode( controller )
+
+    def addNAT( self, name='nat0', connect=True, inNamespace=False,
+                **params):
+        """Add a NAT to the Mininet network
+           name: name of NAT node
+           connect: switch to connect to | True (s1) | None
+           inNamespace: create in a network namespace
+           params: other NAT node params, notably:
+               ip: used as default gateway address"""
+        nat = self.addHost( name, cls=NAT, inNamespace=inNamespace,
                             subnet=self.ipBase, **params )
         # find first switch and create link
         if connect:
-            # connect the nat to the first switch
-            self.addLink( nat, self.switches[ 0 ] )
-            # set the default route on hosts
+            if not isinstance( connect, Node ):
+                # Use first switch if not specified
+                connect = self.switches[ 0 ]
+            # Connect the nat to the switch
+            self.addLink( nat, connect )
+            # Set the default route on hosts
             natIP = nat.params[ 'ip' ].split('/')[ 0 ]
             for host in self.hosts:
                 if host.inNamespace:
@@ -292,9 +339,13 @@ class Mininet( object ):
 
     # Even more convenient syntax for node lookup and iteration
     def __getitem__( self, key ):
-        """net [ name ] operator: Return node(s) with given name(s)"""
+        "net[ name ] operator: Return node with given name"
         return self.nameToNode[ key ]
 
+    def __delitem__( self, key ):
+        "del net[ name ] operator - delete node with given name"
+        self.delNode( self.nameToNode[ key ] )
+
     def __iter__( self ):
         "return iterator over node names"
         for node in chain( self.hosts, self.switches, self.controllers ):
@@ -321,28 +372,65 @@ class Mininet( object ):
         "return (key,value) tuple list for every node in net"
         return zip( self.keys(), self.values() )
 
+    @staticmethod
+    def randMac():
+        "Return a random, non-multicast MAC address"
+        return macColonHex( random.randint(1, 2**48 - 1) & 0xfeffffffffff |
+                            0x020000000000 )
+
     def addLink( self, node1, node2, port1=None, port2=None,
                  cls=None, **params ):
         """"Add a link from node1 to node2
-            node1: source node
-            node2: dest node
-            port1: source port
-            port2: dest port
+            node1: source node (or name)
+            node2: dest node (or name)
+            port1: source port (optional)
+            port2: dest port (optional)
+            cls: link class (optional)
+            params: additional link params (optional)
             returns: link object"""
-        mac1 = macColonHex( random.randint(1, 2**48 - 1) & 0xfeffffffffff  | 0x020000000000 )
-        mac2 = macColonHex( random.randint(1, 2**48 - 1) & 0xfeffffffffff  | 0x020000000000 )
-        defaults = { 'port1': port1,
-                     'port2': port2,
-                     'addr1': mac1,
-                     'addr2': mac2,
-                     'intf': self.intf }
-        defaults.update( params )
-        if not cls:
-            cls = self.link
-        link = cls( node1, node2, **defaults )
+        # Accept node objects or names
+        node1 = node1 if not isinstance( node1, BaseString ) else self[ node1 ]
+        node2 = node2 if not isinstance( node2, BaseString ) else self[ node2 ]
+        options = dict( params )
+        # Port is optional
+        if port1 is not None:
+            options.setdefault( 'port1', port1 )
+        if port2 is not None:
+            options.setdefault( 'port2', port2 )
+        if self.intf is not None:
+            options.setdefault( 'intf', self.intf )
+        # Set default MAC - this should probably be in Link
+        options.setdefault( 'addr1', self.randMac() )
+        options.setdefault( 'addr2', self.randMac() )
+        cls = self.link if cls is None else cls
+        link = cls( node1, node2, **options )
         self.links.append( link )
         return link
 
+    def delLink( self, link ):
+        "Remove a link from this network"
+        link.delete()
+        self.links.remove( link )
+
+    def linksBetween( self, node1, node2 ):
+        "Return Links between node1 and node2"
+        return [ link for link in self.links
+                 if ( node1, node2 ) in (
+                    ( link.intf1.node, link.intf2.node ),
+                    ( link.intf2.node, link.intf1.node ) ) ]
+
+    def delLinkBetween( self, node1, node2, index=0, allLinks=False ):
+        """Delete link(s) between node1 and node2
+           index: index of link to delete if multiple links (0)
+           allLinks: ignore index and delete all such links (False)
+           returns: deleted link(s)"""
+        links = self.linksBetween( node1, node2 )
+        if not allLinks:
+            links = [ links[ index ] ]
+        for link in links:
+            self.delLink( link )
+        return links
+
     def configHosts( self ):
         "Configure a set of hosts."
         for host in self.hosts:
@@ -377,10 +465,10 @@ class Mininet( object ):
             # Add a default controller
             info( '*** Adding controller\n' )
             classes = self.controller
-            if type( classes ) is not list:
+            if not isinstance( classes, list ):
                 classes = [ classes ]
             for i, cls in enumerate( classes ):
-                # Allow Controller objects because nobody understands currying
+                # Allow Controller objects because nobody understands partial()
                 if isinstance( cls, Controller ):
                     self.addController( cls )
                 else:
@@ -393,16 +481,19 @@ class Mininet( object ):
 
         info( '\n*** Adding switches:\n' )
         for switchName in topo.switches():
-            self.addSwitch( switchName, **topo.nodeInfo( switchName) )
+            # A bit ugly: add batch parameter if appropriate
+            params = topo.nodeInfo( switchName)
+            cls = params.get( 'cls', self.switch )
+            if hasattr( cls, 'batchStartup' ):
+                params.setdefault( 'batch', True )
+            self.addSwitch( switchName, **params )
             info( switchName + ' ' )
 
         info( '\n*** Adding links:\n' )
-        for srcName, dstName in topo.links(sort=True):
-            src, dst = self.nameToNode[ srcName ], self.nameToNode[ dstName ]
-            params = topo.linkInfo( srcName, dstName )
-            srcPort, dstPort = topo.port( srcName, dstName )
-            self.addLink( src, dst, srcPort, dstPort, **params )
-            info( '(%s, %s) ' % ( src.name, dst.name ) )
+        for srcName, dstName, params in topo.links(
+                sort=True, withInfo=True ):
+            self.addLink( **params )
+            info( '(%s, %s) ' % ( srcName, dstName ) )
 
         info( '\n' )
 
@@ -455,14 +546,24 @@ class Mininet( object ):
             self.build()
         info( '*** Starting controller\n' )
         for controller in self.controllers:
+            info( controller.name + ' ')
             controller.start()
+        info( '\n' )
         info( '*** Starting %s switches\n' % len( self.switches ) )
         for switch in self.switches:
             info( switch.name + ' ')
             switch.start( self.controllers )
+        started = {}
+        for swclass, switches in groupby(
+                sorted( self.switches,
+                        key=lambda s: str( type( s ) ) ), type ):
+            switches = tuple( switches )
+            if hasattr( swclass, 'batchStartup' ):
+                success = swclass.batchStartup( switches )
+                started.update( { s: s for s in success } )
         info( '\n' )
         if self.waitConn:
-            self.waitConnected()
+            self.waitConnected( self.waitConn )
 
     def stop( self ):
         "Stop the controller(s), switches and hosts"
@@ -471,22 +572,33 @@ class Mininet( object ):
             info( controller.name + ' ' )
             controller.stop()
         info( '\n' )
+        # Unlimit cfs hosts to speed up shutdown
+        for h in self.hosts:
+            if hasattr( h, 'unlimit' ):
+                h.unlimit()
         if self.terms:
             info( '*** Stopping %i terms\n' % len( self.terms ) )
             self.stopXterms()
-        info( '*** Stopping %i switches\n' % len( self.switches ) )
-        for swclass, switches in groupby( sorted( self.switches, key=type ), type ):
-            if hasattr( swclass, 'batchShutdown' ):
-                swclass.batchShutdown( switches )
-        for switch in self.switches:
-            info( switch.name + ' ' )
-            switch.stop()
-            switch.terminate()
-        info( '\n' )
         info( '*** Stopping %i links\n' % len( self.links ) )
         for link in self.links:
+            info( '.' )
             link.stop()
         info( '\n' )
+        info( '*** Stopping %i switches\n' % len( self.switches ) )
+        stopped = {}
+        for swclass, switches in groupby(
+                sorted( self.switches,
+                        key=lambda s: str( type( s ) ) ), type ):
+            switches = tuple( switches )
+            if hasattr( swclass, 'batchShutdown' ):
+                success = swclass.batchShutdown( switches )
+                stopped.update( { s: s for s in success } )
+        for switch in self.switches:
+            info( switch.name + ' ' )
+            if switch not in stopped:
+                switch.stop()
+            switch.terminate()
+        info( '\n' )
         info( '*** Stopping %i hosts\n' % len( self.hosts ) )
         for host in self.hosts:
             info( host.name + ' ' )
@@ -510,13 +622,13 @@ class Mininet( object ):
         if hosts is None:
             hosts = self.hosts
         poller = select.poll()
-        Node = hosts[ 0 ]  # so we can call class method fdToNode
+        h1 = hosts[ 0 ]  # so we can call class method fdToNode
         for host in hosts:
             poller.register( host.stdout )
         while True:
             ready = poller.poll( timeoutms )
             for fd, event in ready:
-                host = Node.fdToNode( fd )
+                host = h1.fdToNode( fd )
                 if event & select.POLLIN:
                     line = host.readline()
                     if line is not None:
@@ -534,7 +646,7 @@ class Mininet( object ):
         # Check for downed link
         if 'connect: Network is unreachable' in pingOutput:
             return 1, 0
-        r = r'(\d+) packets transmitted, (\d+) received'
+        r = r'(\d+) packets transmitted, (\d+)( packets)? received'
         m = re.search( r, pingOutput )
         if m is None:
             error( '*** Error: could not parse ping output: %s\n' %
@@ -563,7 +675,8 @@ class Mininet( object ):
                     if timeout:
                         opts = '-W %s' % timeout
                     if dest.intfs:
-                        result = node.cmd( 'ping -c1 %s %s' % (opts, dest.IP()) )
+                        result = node.cmd( 'LANG=C ping -c1 %s %s' %
+                                           (opts, dest.IP()) )
                         sent, received = self._parsePing( result )
                     else:
                         sent, received = 0, 0
@@ -595,7 +708,7 @@ class Mininet( object ):
         m = re.search( r, pingOutput )
         if m is not None:
             return errorTuple
-        r = r'(\d+) packets transmitted, (\d+) received'
+        r = r'(\d+) packets transmitted, (\d+)( packets)? received'
         m = re.search( r, pingOutput )
         if m is None:
             error( '*** Error: could not parse ping output: %s\n' %
@@ -673,65 +786,76 @@ class Mininet( object ):
         return self.pingFull( hosts=hosts )
 
     @staticmethod
-    def _parseIperf( iperfOutput ):
-        """Parse iperf output and return bandwidth.
-           iperfOutput: string
-           returns: result string"""
-        r = r'([\d\.]+ \w+/sec)'
-        m = re.findall( r, iperfOutput )
-        if m:
-            return m[-1]
-        else:
-            # was: raise Exception(...)
-            error( 'could not parse iperf output: ' + iperfOutput )
-            return ''
+    def _iperfVals( iperfcsv, serverip ):
+        """Return iperf CSV as dict
+           iperfcsv: iperf -y C output
+           serverip: iperf server IP address
+        """
+        fields = 'date cip cport sip sport ipver interval sent rate'
+        lines = iperfcsv.strip().split('\n')
+        svals = {}
+        for line in lines:
+            if ',' not in line:
+                continue
+            line = line.split( ',' )
+            svals = dict( zip( fields.split(), line ) )
+            # Return client in cip:cport, server in sip:sport
+            if svals[ 'cip' ] == serverip:
+                svals[ 'cip' ], svals[ 'sip' ] = (
+                    svals[ 'sip' ], svals[ 'cip' ] )
+                svals[ 'cport' ], svals[ 'sport' ] = (
+                    svals[ 'sport' ], svals[ 'cport' ] )
+        return svals
 
     # XXX This should be cleaned up
 
-    def iperf( self, hosts=None, l4Type='TCP', udpBw='10M', format=None ):
+    def iperf( self, hosts=None, l4Type='TCP', udpBw='10M', fmt=None,
+               seconds=5, port=5001):
         """Run iperf between two hosts.
-           hosts: list of hosts; if None, uses opposite hosts
+           hosts: list of hosts; if None, uses first and last hosts
            l4Type: string, one of [ TCP, UDP ]
-           returns: results two-element array of [ server, client ] speeds
+           udpBw: bandwidth target for UDP test
+           fmt: scale/format argument (e.g. m/M for Mbps)
+           seconds: iperf time to transmit
+           port: iperf port
+           returns: two-element array of [ server, client ] speeds
            note: send() is buffered, so client rate can be much higher than
            the actual transmission rate; on an unloaded system, server
            rate should be much closer to the actual receive rate"""
-        if not quietRun( 'which telnet' ):
-            error( 'Cannot find telnet in $PATH - required for iperf test' )
-            return
-        if not hosts:
-            hosts = [ self.hosts[ 0 ], self.hosts[ -1 ] ]
-        else:
-            assert len( hosts ) == 2
+        hosts = hosts or [ self.hosts[ 0 ], self.hosts[ -1 ] ]
+        assert len( hosts ) == 2
         client, server = hosts
-        output( '*** Iperf: testing ' + l4Type + ' bandwidth between ' )
-        output( "%s and %s\n" % ( client.name, server.name ) )
+        output( '*** Iperf: testing', l4Type, 'bandwidth between',
+                client, 'and', server, '\n' )
         server.cmd( 'killall -9 iperf' )
-        iperfArgs = 'iperf '
+        # Note: CSV mode
+        iperfArgs = 'iperf -y C -p %d ' % port
         bwArgs = ''
         if l4Type == 'UDP':
             iperfArgs += '-u '
             bwArgs = '-b ' + udpBw + ' '
-        elif l4Type != 'TCP':
-            raise Exception( 'Unexpected l4 type: %s' % l4Type )
-        if format:
-          iperfArgs += '-f %s ' %format
-        server.sendCmd( iperfArgs + '-s', printPid=True )
-        servout = ''
-        while server.lastPid is None:
-            servout += server.monitor()
+        server.sendCmd( iperfArgs + '-s' )
+        serverip = server.IP()
         if l4Type == 'TCP':
-            while 'Connected' not in client.cmd(
-                    'sh -c "echo A | telnet -e A %s 5001"' % server.IP()):
-                info( 'Waiting for iperf to start up...' )
-                sleep(.5)
-        cliout = client.cmd( iperfArgs + '-t 5 -c ' + server.IP() + ' ' +
-                             bwArgs )
-        debug( 'Client output: %s\n' % cliout )
+            if not waitListening( client, serverip, port ):
+                raise Exception( 'Could not connect to iperf on port %d'
+                                 % port )
+        cliout = client.cmd( iperfArgs + '-t %d -c ' % seconds +
+                             server.IP() + ' ' + bwArgs )
+        cvals = self._iperfVals( cliout, serverip )
+        serverout = ''
+        # Wait for output from the client session
+        while True:
+            serverout += server.monitor( timeoutms=5000 )
+            svals = self._iperfVals( serverout, serverip )
+            # Check for the client's source/output port
+            if ( svals and cvals[ 'sport' ] == svals[ 'sport' ]
+                 and int( svals[ 'rate' ] ) > 0 ):
+                break
         server.sendInt()
-        servout += server.waitOutput()
-        debug( 'Server output: %s\n' % servout )
-        result = [ self._parseIperf( servout ), self._parseIperf( cliout ) ]
+        serverout += server.waitOutput()
+        result = [ fmtBps( svals[ 'rate'], fmt ),
+                   fmtBps( cvals[ 'rate' ], fmt ) ]
         if l4Type == 'UDP':
             result.insert( 0, udpBw )
         output( '*** Results: %s\n' % result )
@@ -740,10 +864,9 @@ class Mininet( object ):
     def runCpuLimitTest( self, cpu, duration=5 ):
         """run CPU limit test with 'while true' processes.
         cpu: desired CPU fraction of each host
-        duration: test duration in seconds
+        duration: test duration in seconds (integer)
         returns a single list of measured CPU fractions as floats.
         """
-        cores = int( quietRun( 'nproc' ) )
         pct = cpu * 100
         info( '*** Testing CPU %.0f%% bandwidth limit\n' % pct )
         hosts = self.hosts
@@ -761,12 +884,14 @@ class Mininet( object ):
         # get the initial cpu time for each host
         for host in hosts:
             outputs[ host ] = []
-            with open( '/sys/fs/cgroup/cpuacct/%s/cpuacct.usage' % host, 'r' ) as f:
+            with open( '/sys/fs/cgroup/cpuacct/%s/cpuacct.usage' %
+                       host, 'r' ) as f:
                 time[ host ] = float( f.read() )
-        for _ in range( 5 ):
+        for _ in range( duration ):
             sleep( 1 )
             for host in hosts:
-                with open( '/sys/fs/cgroup/cpuacct/%s/cpuacct.usage' % host, 'r' ) as f:
+                with open( '/sys/fs/cgroup/cpuacct/%s/cpuacct.usage' %
+                           host, 'r' ) as f:
                     readTime = float( f.read() )
                 outputs[ host ].append( ( ( readTime - time[ host ] )
                                         / 1000000000 ) / cores * 100 )
@@ -793,10 +918,8 @@ class Mininet( object ):
         elif dst not in self.nameToNode:
             error( 'dst not in network: %s\n' % dst )
         else:
-            if type( src ) is str:
-                src = self.nameToNode[ src ]
-            if type( dst ) is str:
-                dst = self.nameToNode[ dst ]
+            src = self.nameToNode[ src ]
+            dst = self.nameToNode[ dst ]
             connections = src.connectionsTo( dst )
             if len( connections ) == 0:
                 error( 'src and dst not connected: %s %s\n' % ( src, dst) )

mininet/nodelib.py

@@ -5,7 +5,10 @@ This contains additional Node types which you may find to be useful.
 """
 
 from mininet.node import Node, Switch
-from mininet.log import setLogLevel, info
+from mininet.log import info, warn
+from mininet.moduledeps import pathCheck
+from mininet.util import quietRun
+
 
 class LinuxBridge( Switch ):
     "Linux Bridge (with optional spanning tree)"
@@ -29,8 +32,9 @@ class LinuxBridge( Switch ):
             return 'forwarding' in self.cmd( 'brctl showstp', self )
         else:
             return True
-    
-    def start( self, controllers ):
+
+    def start( self, _controllers ):
+        "Start Linux bridge"
         self.cmd( 'ifconfig', self, 'down' )
         self.cmd( 'brctl delbr', self )
         self.cmd( 'brctl addbr', self )
@@ -42,74 +46,109 @@ class LinuxBridge( Switch ):
                 self.cmd( 'brctl addif', self, i )
         self.cmd( 'ifconfig', self, 'up' )
 
-    def stop( self ):
+    def stop( self, deleteIntfs=True ):
+        """Stop Linux bridge
+           deleteIntfs: delete interfaces? (True)"""
         self.cmd( 'ifconfig', self, 'down' )
         self.cmd( 'brctl delbr', self )
+        super( LinuxBridge, self ).stop( deleteIntfs )
+
+    def dpctl( self, *args ):
+        "Run brctl command"
+        return self.cmd( 'brctl', *args )
+
+    @classmethod
+    def setup( cls ):
+        "Check dependencies and warn about firewalling"
+        pathCheck( 'brctl', moduleName='bridge-utils' )
+        # Disable Linux bridge firewalling so that traffic can flow!
+        for table in 'arp', 'ip', 'ip6':
+            cmd = 'sysctl net.bridge.bridge-nf-call-%stables' % table
+            out = quietRun( cmd ).strip()
+            if out.endswith( '1' ):
+                warn( 'Warning: Linux bridge may not work with', out, '\n' )
+
 
 class NAT( Node ):
-    """NAT: Provides connectivity to external network"""
+    "NAT: Provides connectivity to external network"
 
-    def __init__( self, name, inetIntf='eth0', subnet='10.0/8', localIntf=None, **params):
+    def __init__( self, name, subnet='10.0/8',
+                  localIntf=None, flush=False, **params):
+        """Start NAT/forwarding between Mininet and external network
+           subnet: Mininet subnet (default 10.0/8)
+           flush: flush iptables before installing NAT rules"""
         super( NAT, self ).__init__( name, **params )
 
-        """Start NAT/forwarding between Mininet and external network
-        inetIntf: interface for internet access
-        subnet: Mininet subnet (default 10.0/8)="""
-        self.inetIntf = inetIntf
         self.subnet = subnet
         self.localIntf = localIntf
+        self.flush = flush
+        self.forwardState = self.cmd( 'sysctl -n net.ipv4.ip_forward' ).strip()
 
+    def setManualConfig( self, intf ):
+        """Prevent network-manager/networkd from messing with our interface
+           by specifying manual configuration in /etc/network/interfaces"""
+        cfile = '/etc/network/interfaces'
+        line = '\niface %s inet manual\n' % intf
+        try:
+            with open( cfile ) as f:
+                config = f.read()
+        except IOError:
+            config = ''
+        if ( line ) not in config:
+            info( '*** Adding "' + line.strip() + '" to ' + cfile + '\n' )
+            with open( cfile, 'a' ) as f:
+                f.write( line )
+            # Probably need to restart network manager to be safe -
+            # hopefully this won't disconnect you
+            self.cmd( 'service network-manager restart || netplan apply' )
+
+    # pylint: disable=arguments-differ
     def config( self, **params ):
-        super( NAT, self).config( **params )
         """Configure the NAT and iptables"""
 
         if not self.localIntf:
-            self.localIntf =  self.defaultIntf()
+            self.localIntf = self.defaultIntf()
 
-        self.cmd( 'sysctl net.ipv4.ip_forward=0' )
+        self.setManualConfig( self.localIntf )
 
-        # Flush any currently active rules
-        # TODO: is this safe?
-        self.cmd( 'iptables -F' )
-        self.cmd( 'iptables -t nat -F' )
+        # Now we can configure manually without interference
+        super( NAT, self).config( **params )
 
-        # Create default entries for unmatched traffic
-        self.cmd( 'iptables -P INPUT ACCEPT' )
-        self.cmd( 'iptables -P OUTPUT ACCEPT' )
-        self.cmd( 'iptables -P FORWARD DROP' )
+        if self.flush:
+            self.cmd( 'sysctl net.ipv4.ip_forward=0' )
+            self.cmd( 'iptables -F' )
+            self.cmd( 'iptables -t nat -F' )
+            # Create default entries for unmatched traffic
+            self.cmd( 'iptables -P INPUT ACCEPT' )
+            self.cmd( 'iptables -P OUTPUT ACCEPT' )
+            self.cmd( 'iptables -P FORWARD DROP' )
 
-        # Configure NAT
-        self.cmd( 'iptables -I FORWARD -i', self.localIntf, '-d', self.subnet, '-j DROP' )
-        self.cmd( 'iptables -A FORWARD -i', self.localIntf, '-s', self.subnet, '-j ACCEPT' )
-        self.cmd( 'iptables -A FORWARD -i', self.inetIntf, '-d', self.subnet, '-j ACCEPT' )
-        self.cmd( 'iptables -t nat -A POSTROUTING -o ', self.inetIntf, '-j MASQUERADE' )
+        # Install NAT rules
+        self.cmd( 'iptables -I FORWARD',
+                  '-i', self.localIntf, '-d', self.subnet, '-j DROP' )
+        self.cmd( 'iptables -A FORWARD',
+                  '-i', self.localIntf, '-s', self.subnet, '-j ACCEPT' )
+        self.cmd( 'iptables -A FORWARD',
+                  '-o', self.localIntf, '-d', self.subnet, '-j ACCEPT' )
+        self.cmd( 'iptables -t nat -A POSTROUTING',
+                  '-s', self.subnet, "'!'", '-d', self.subnet,
+                  '-j MASQUERADE' )
 
         # Instruct the kernel to perform forwarding
         self.cmd( 'sysctl net.ipv4.ip_forward=1' )
 
-        # Prevent network-manager from messing with our interface
-        # by specifying manual configuration in /etc/network/interfaces
-        intf = self.localIntf
-        cfile = '/etc/network/interfaces'
-        line = '\niface %s inet manual\n' % intf
-        config = open( cfile ).read()
-        if ( line ) not in config:
-            info( '*** Adding "' + line.strip() + '" to ' + cfile )
-            with open( cfile, 'a' ) as f:
-                f.write( line )
-        # Probably need to restart network-manager to be safe -
-        # hopefully this won't disconnect you
-        self.cmd( 'service network-manager restart' )
-
     def terminate( self ):
-        """Stop NAT/forwarding between Mininet and external network"""
-        # Flush any currently active rules
-        # TODO: is this safe?
-        self.cmd( 'iptables -F' )
-        self.cmd( 'iptables -t nat -F' )
-
-        # Instruct the kernel to stop forwarding
-        self.cmd( 'sysctl net.ipv4.ip_forward=0' )
-
+        "Stop NAT/forwarding between Mininet and external network"
+        # Remote NAT rules
+        self.cmd( 'iptables -D FORWARD',
+                   '-i', self.localIntf, '-d', self.subnet, '-j DROP' )
+        self.cmd( 'iptables -D FORWARD',
+                  '-i', self.localIntf, '-s', self.subnet, '-j ACCEPT' )
+        self.cmd( 'iptables -D FORWARD',
+                  '-o', self.localIntf, '-d', self.subnet, '-j ACCEPT' )
+        self.cmd( 'iptables -t nat -D POSTROUTING',
+                  '-s', self.subnet, '\'!\'', '-d', self.subnet,
+                  '-j MASQUERADE' )
+        # Put the forwarding state back to what it was
+        self.cmd( 'sysctl net.ipv4.ip_forward=%s' % self.forwardState )
         super( NAT, self ).terminate()
-

mininet/term.py

@@ -32,16 +32,16 @@ def tunnelX11( node, display=None):
         port = 6000 + int( float( screen ) )
         connection = r'TCP\:%s\:%s' % ( host, port )
         cmd = [ "socat", "TCP-LISTEN:%d,fork,reuseaddr" % port,
-               "EXEC:'mnexec -a 1 socat STDIO %s'" % connection ]
+                "EXEC:'mnexec -a 1 socat STDIO %s'" % connection ]
     return 'localhost:' + screen, node.popen( cmd )
 
-def makeTerm( node, title='Node', term='xterm', display=None ):
+def makeTerm( node, title='Node', term='xterm', display=None, cmd='bash'):
     """Create an X11 tunnel to the node and start up a terminal.
        node: Node object
        title: base title
        term: 'xterm' or 'gterm'
        returns: two Popen objects, tunnel and terminal"""
-    title += ': ' + node.name
+    title = '"%s: %s"' % ( title, node.name )
     if not node.inNamespace:
         title += ' (root)'
     cmds = {
@@ -50,11 +50,12 @@ def makeTerm( node, title='Node', term='xterm', display=None ):
     }
     if term not in cmds:
         error( 'invalid terminal type: %s' % term )
-        return
+        return None
     display, tunnel = tunnelX11( node, display )
     if display is None:
         return []
-    term = node.popen( cmds[ term ] + [ display, '-e', 'env TERM=ansi bash'] )
+    term = node.popen( cmds[ term ] +
+                       [ display, '-e', 'env TERM=ansi %s' % cmd ] )
     return [ tunnel, term ] if tunnel else [ term ]
 
 def runX11( node, cmd ):

mininet/test/runner.py

@@ -6,7 +6,7 @@ Run all mininet core tests
  -quick : skip tests that take more than ~30 seconds
 """
 
-import unittest
+from unittest import defaultTestLoader, TextTestRunner
 import os
 import sys
 from mininet.util import ensureRoot
@@ -19,13 +19,16 @@ def runTests( testDir, verbosity=1 ):
     ensureRoot()
     cleanup()
     # discover all tests in testDir
-    testSuite = unittest.defaultTestLoader.discover( testDir )
+    testSuite = defaultTestLoader.discover( testDir )
     # run tests
-    unittest.TextTestRunner( verbosity=verbosity ).run( testSuite )
+    success = ( TextTestRunner( verbosity=verbosity )
+                .run( testSuite ).wasSuccessful() )
+    sys.exit( 0 if success else 1 )
+
 
 if __name__ == '__main__':
     setLogLevel( 'warning' )
     # get the directory containing example tests
-    testDir = os.path.dirname( os.path.realpath( __file__ ) )
-    verbosity = 2 if '-v' in sys.argv else 1
-    runTests( testDir, verbosity )
+    thisdir = os.path.dirname( os.path.realpath( __file__ ) )
+    vlevel = 2 if '-v' in sys.argv else 1
+    runTests( testDir=thisdir, verbosity=vlevel )

mininet/test/test_hifi.py

@@ -4,6 +4,7 @@
    Test creation and pings for topologies with link and/or CPU options."""
 
 import unittest
+import sys
 from functools import partial
 
 from mininet.net import Mininet
@@ -13,6 +14,7 @@ from mininet.link import TCLink
 from mininet.topo import Topo
 from mininet.log import setLogLevel
 from mininet.util import quietRun
+from mininet.clean import cleanup
 
 # Number of hosts for each test
 N = 2
@@ -38,7 +40,13 @@ class testOptionsTopoCommon( object ):
     """Verify ability to create networks with host and link options
        (common code)."""
 
-    switchClass = None # overridden in subclasses
+    switchClass = None  # overridden in subclasses
+
+    @staticmethod
+    def tearDown():
+        "Clean up if necessary"
+        if sys.exc_info() != ( None, None, None ):
+            cleanup()
 
     def runOptionsTopoTest( self, n, msg, hopts=None, lopts=None ):
         "Generic topology-with-options test runner."
@@ -79,7 +87,7 @@ class testOptionsTopoCommon( object ):
                      upperBound, lowerBound ) )
         msg += info
 
-        self.assertGreaterEqual( float( measured ),lowerBound, msg=msg )
+        self.assertGreaterEqual( float( measured ), lowerBound, msg=msg )
         self.assertLessEqual( float( measured ), upperBound, msg=msg )
 
     def testCPULimits( self ):
@@ -87,7 +95,7 @@ class testOptionsTopoCommon( object ):
         CPU_FRACTION = 0.1
         CPU_TOLERANCE = 0.8  # CPU fraction below which test should fail
         hopts = { 'cpu': CPU_FRACTION }
-        #self.runOptionsTopoTest( N, hopts=hopts )
+        # self.runOptionsTopoTest( N, hopts=hopts )
 
         mn = Mininet( SingleSwitchOptionsTopo( n=N, hopts=hopts ),
                       host=CPULimitedHost, switch=self.switchClass,
@@ -96,7 +104,8 @@ class testOptionsTopoCommon( object ):
         results = mn.runCpuLimitTest( cpu=CPU_FRACTION )
         mn.stop()
         hostUsage = '\n'.join( 'h%s: %s' %
-                               ( n + 1, results[ ( n - 1 ) * 5: ( n * 5 ) - 1 ] )
+                               ( n + 1,
+                                 results[ (n - 1) * 5 : (n * 5) - 1 ] )
                                for n in range( N ) )
         hoptsStr = ', '.join( '%s: %s' % ( opt, value )
                               for opt, value in hopts.items() )
@@ -106,16 +115,18 @@ class testOptionsTopoCommon( object ):
                 'hopts = %s\n'
                 'host = CPULimitedHost\n'
                 'Switch = %s\n'
-                % ( CPU_FRACTION * 100, hostUsage, N, hoptsStr, self.switchClass ) )
+                % ( CPU_FRACTION * 100, hostUsage, N, hoptsStr,
+                    self.switchClass ) )
         for pct in results:
-            #divide cpu by 100 to convert from percentage to fraction
+            # divide cpu by 100 to convert from percentage to fraction
             self.assertWithinTolerance( pct/100, CPU_FRACTION,
                                         CPU_TOLERANCE, msg )
 
     def testLinkBandwidth( self ):
         "Verify that link bandwidths are accurate within a bound."
         if self.switchClass is UserSwitch:
-            self.skipTest ( 'UserSwitch has very poor performance, so skip for now' )
+            self.skipTest( 'UserSwitch has very poor performance -'
+                           ' skipping for now' )
         BW = 5  # Mbps
         BW_TOLERANCE = 0.8  # BW fraction below which test should fail
         # Verify ability to create limited-link topo first;
@@ -124,7 +135,7 @@ class testOptionsTopoCommon( object ):
         mn = Mininet( SingleSwitchOptionsTopo( n=N, lopts=lopts ),
                       link=TCLink, switch=self.switchClass,
                       waitConnected=True )
-        bw_strs = mn.run( mn.iperf, format='m' )
+        bw_strs = mn.run( mn.iperf, fmt='m' )
         loptsStr = ', '.join( '%s: %s' % ( opt, value )
                               for opt, value in lopts.items() )
         msg = ( '\nTesting link bandwidth limited to %d Mbps per link\n'
@@ -141,7 +152,7 @@ class testOptionsTopoCommon( object ):
         # As long as the kernel doesn't wait a long time before
         # delivering bytes to the iperf server, its reported data rate
         # should be close to the actual receive rate.
-        serverRate, clientRate = bw_strs
+        serverRate, _clientRate = bw_strs
         bw = float( serverRate.split(' ')[0] )
         self.assertWithinTolerance( bw, BW, BW_TOLERANCE, msg )
 
@@ -160,12 +171,12 @@ class testOptionsTopoCommon( object ):
         mn.stop()
         test_outputs = ping_delays[0]
         # Ignore unused variables below
-        # pylint: disable-msg=W0612
+        # pylint: disable=W0612
         node, dest, ping_outputs = test_outputs
         sent, received, rttmin, rttavg, rttmax, rttdev = ping_outputs
         pingFailMsg = 'sent %s pings, only received %s' % ( sent, received )
         self.assertEqual( sent, received, msg=pingFailMsg )
-        # pylint: enable-msg=W0612
+        # pylint: enable=W0612
         loptsStr = ', '.join( '%s: %s' % ( opt, value )
                               for opt, value in lopts.items() )
         msg = ( '\nTesting Link Delay of %s ms\n'
@@ -181,10 +192,9 @@ class testOptionsTopoCommon( object ):
 
         for rttval in [rttmin, rttavg, rttmax]:
             # Multiply delay by 4 to cover there & back on two links
-            self.assertWithinTolerance( rttval, DELAY_MS * 4.0, 
+            self.assertWithinTolerance( rttval, DELAY_MS * 4.0,
                                         DELAY_TOLERANCE, msg )
 
-
     def testLinkLoss( self ):
         "Verify that we see packet drops with a high configured loss rate."
         LOSS_PERCENT = 99
@@ -212,7 +222,8 @@ class testOptionsTopoCommon( object ):
                 'lopts = %s\n'
                 'host = default\n'
                 'switch = %s\n'
-                % ( LOSS_PERCENT, dropped_total, N, loptsStr, self.switchClass ) )
+                % ( LOSS_PERCENT, dropped_total, N, loptsStr,
+                    self.switchClass ) )
 
         self.assertGreater( dropped_total, 0, msg )
 
@@ -245,12 +256,14 @@ class testOptionsTopoIVS( testOptionsTopoCommon, unittest.TestCase ):
     switchClass = IVSSwitch
 
 @unittest.skipUnless( quietRun( 'which ofprotocol' ),
-                     'Reference user switch is not installed' )
+                      'Reference user switch is not installed' )
 class testOptionsTopoUserspace( testOptionsTopoCommon, unittest.TestCase ):
-    "Verify ability to create networks with host and link options (UserSwitch)."
+    """Verify ability to create networks with host and link options
+     (UserSwitch)."""
     longMessage = True
     switchClass = UserSwitch
 
+
 if __name__ == '__main__':
     setLogLevel( 'warning' )
     unittest.main()

mininet/test/test_nets.py

@@ -4,6 +4,7 @@
    Test creation and all-pairs ping for each included mininet topo type."""
 
 import unittest
+import sys
 from functools import partial
 
 from mininet.net import Mininet
@@ -12,6 +13,7 @@ from mininet.node import UserSwitch, OVSSwitch, IVSSwitch
 from mininet.topo import SingleSwitchTopo, LinearTopo
 from mininet.log import setLogLevel
 from mininet.util import quietRun
+from mininet.clean import cleanup
 
 # Tell pylint not to complain about calls to other class
 # pylint: disable=E1101
@@ -19,7 +21,13 @@ from mininet.util import quietRun
 class testSingleSwitchCommon( object ):
     "Test ping with single switch topology (common code)."
 
-    switchClass = None # overridden in subclasses
+    switchClass = None  # overridden in subclasses
+
+    @staticmethod
+    def tearDown():
+        "Clean up if necessary"
+        if sys.exc_info() != ( None, None, None ):
+            cleanup()
 
     def testMinimal( self ):
         "Ping test on minimal topology"
@@ -51,7 +59,7 @@ class testSingleSwitchIVS( testSingleSwitchCommon, unittest.TestCase ):
     switchClass = IVSSwitch
 
 @unittest.skipUnless( quietRun( 'which ofprotocol' ),
-                     'Reference user switch is not installed' )
+                      'Reference user switch is not installed' )
 class testSingleSwitchUserspace( testSingleSwitchCommon, unittest.TestCase ):
     "Test ping with single switch topology (Userspace switch)."
     switchClass = UserSwitch
@@ -63,11 +71,12 @@ class testSingleSwitchUserspace( testSingleSwitchCommon, unittest.TestCase ):
 class testLinearCommon( object ):
     "Test all-pairs ping with LinearNet (common code)."
 
-    switchClass = None # overridden in subclasses
+    switchClass = None  # overridden in subclasses
 
     def testLinear5( self ):
         "Ping test on a 5-switch topology"
-        mn = Mininet( LinearTopo( k=5 ), self.switchClass, Host, Controller, waitConnected=True )
+        mn = Mininet( LinearTopo( k=5 ), self.switchClass, Host,
+                      Controller, waitConnected=True )
         dropped = mn.run( mn.ping )
         self.assertEqual( dropped, 0 )
 

mininet/test/test_ptyleak.py

@@ -0,0 +1,32 @@
+#!/usr/bin/env python
+
+"""
+Regression test for pty leak in Node()
+"""
+
+import unittest
+
+from mininet.net import Mininet
+from mininet.clean import cleanup
+from mininet.topo import SingleSwitchTopo
+
+class TestPtyLeak( unittest.TestCase ):
+    "Verify that there is no pty leakage"
+
+    @staticmethod
+    def testPtyLeak():
+        "Test for pty leakage"
+        net = Mininet( SingleSwitchTopo() )
+        net.start()
+        host = net[ 'h1' ]
+        for _ in range( 0, 10 ):
+            oldptys = host.slave, host.master
+            net.delHost( host )
+            host = net.addHost( 'h1' )
+            assert ( host.slave, host.master ) == oldptys
+        net.stop()
+
+
+if __name__ == '__main__':
+    unittest.main()
+    cleanup()

mininet/test/test_switchdpidassignment.py

@@ -0,0 +1,102 @@
+#!/usr/bin/env python
+
+"""Package: mininet
+   Regression tests for switch dpid assignment."""
+
+import unittest
+import sys
+
+from mininet.net import Mininet
+from mininet.node import Host, Controller
+from mininet.node import ( UserSwitch, OVSSwitch, IVSSwitch )
+from mininet.topo import Topo
+from mininet.log import setLogLevel
+from mininet.util import quietRun
+from mininet.clean import cleanup
+
+
+class TestSwitchDpidAssignmentOVS( unittest.TestCase ):
+    "Verify Switch dpid assignment."
+
+    switchClass = OVSSwitch  # overridden in subclasses
+
+    def tearDown( self ):
+        "Clean up if necessary"
+        # satisfy pylint
+        assert self
+        if sys.exc_info() != ( None, None, None ):
+            cleanup()
+
+    def testDefaultDpid( self ):
+        """Verify that the default dpid is assigned using a valid provided
+        canonical switchname if no dpid is passed in switch creation."""
+        net = Mininet( Topo(), self.switchClass, Host, Controller )
+        switch = net.addSwitch( 's1' )
+        self.assertEqual( switch.defaultDpid(), switch.dpid )
+        net.stop()
+
+    def dpidFrom( self, num ):
+        "Compute default dpid from number"
+        fmt = ( '%0' + str( self.switchClass.dpidLen ) + 'x' )
+        return fmt % num
+
+    def testActualDpidAssignment( self ):
+        """Verify that Switch dpid is the actual dpid assigned if dpid is
+        passed in switch creation."""
+        dpid = self.dpidFrom( 0xABCD )
+        net = Mininet( Topo(), self.switchClass, Host, Controller )
+        switch = net.addSwitch( 's1', dpid=dpid )
+        self.assertEqual( switch.dpid, dpid )
+        net.stop()
+
+    def testDefaultDpidAssignmentFailure( self ):
+        """Verify that Default dpid assignment raises an Exception if the
+        name of the switch does not contin a digit. Also verify the
+        exception message."""
+        net = Mininet( Topo(), self.switchClass, Host, Controller )
+        with self.assertRaises( Exception ) as raises_cm:
+            net.addSwitch( 'A' )
+        self.assertTrue( 'Unable to derive '
+                         'default datapath ID - please either specify a dpid '
+                         'or use a canonical switch name such as s23.'
+                         in str( raises_cm.exception ) )
+        net.stop()
+
+    def testDefaultDpidLen( self ):
+        """Verify that Default dpid length is 16 characters consisting of
+        16 - len(hex of first string of contiguous digits passed in switch
+        name) 0's followed by hex of first string of contiguous digits passed
+        in switch name."""
+        net = Mininet( Topo(), self.switchClass, Host, Controller )
+        switch = net.addSwitch( 's123' )
+        self.assertEqual( switch.dpid, self.dpidFrom( 123 ) )
+        net.stop()
+
+
+class OVSUser( OVSSwitch):
+    "OVS User Switch convenience class"
+    def __init__( self, *args, **kwargs ):
+        kwargs.update( datapath='user' )
+        OVSSwitch.__init__( self, *args, **kwargs )
+
+class testSwitchOVSUser( TestSwitchDpidAssignmentOVS ):
+    "Test dpid assignnment of OVS User Switch."
+    switchClass = OVSUser
+
+@unittest.skipUnless( quietRun( 'which ivs-ctl' ),
+                      'IVS switch is not installed' )
+class testSwitchIVS( TestSwitchDpidAssignmentOVS ):
+    "Test dpid assignment of IVS switch."
+    switchClass = IVSSwitch
+
+@unittest.skipUnless( quietRun( 'which ofprotocol' ),
+                      'Reference user switch is not installed' )
+class testSwitchUserspace( TestSwitchDpidAssignmentOVS ):
+    "Test dpid assignment of Userspace switch."
+    switchClass = UserSwitch
+
+
+if __name__ == '__main__':
+    setLogLevel( 'warning' )
+    unittest.main()
+    cleanup()

mininet/test/test_util.py

@@ -0,0 +1,40 @@
+#!/usr/bin/env python
+
+"""Package: mininet
+   Test functions defined in mininet.util."""
+
+import unittest
+
+from mininet.util import quietRun
+
+class testQuietRun( unittest.TestCase ):
+    """Test quietRun that runs a command and returns its merged output from
+    STDOUT and STDIN"""
+
+    @staticmethod
+    def getEchoCmd( n ):
+        "Return a command that will print n characters"
+        return "echo -n " + "x" * n
+
+    def testEmpty( self ):
+        "Run a command that prints nothing"
+        output = quietRun(testQuietRun.getEchoCmd( 0 ) )
+        self.assertEqual( 0, len( output ) )
+
+    def testOneRead( self ):
+        """Run a command whose output is entirely read on the first call if
+        each call reads at most 1024 characters
+        """
+        for n in [ 42, 1024 ]:
+            output = quietRun( testQuietRun.getEchoCmd( n ) )
+            self.assertEqual( n, len( output ) )
+
+    def testMultipleReads( self ):
+        "Run a command whose output is not entirely read on the first read"
+        for n in [ 1025, 4242 ]:
+            output = quietRun(testQuietRun.getEchoCmd( n ) )
+            self.assertEqual( n, len( output ) )
+
+
+if __name__ == "__main__":
+    unittest.main()

mininet/test/test_walkthrough.py

@@ -6,22 +6,35 @@ Tests for the Mininet Walkthrough
 TODO: missing xterm test
 """
 
-import unittest
-import pexpect
 import os
 import re
-from mininet.util import quietRun
-from distutils.version import StrictVersion
+import unittest
+
+from sys import stdout
+
+from mininet.util import quietRun, pexpect, StrictVersion
+from mininet.clean import cleanup
+
 
 def tsharkVersion():
+    "Return tshark version"
     versionStr = quietRun( 'tshark -v' )
-    versionMatch = re.findall( 'TShark \d+.\d+.\d+', versionStr )[0]
-    return versionMatch.split()[ 1 ]
+    versionMatch = re.findall( r'TShark[^\d]*(\d+.\d+.\d+)', versionStr )
+    return versionMatch[ 0 ]
+
+# pylint doesn't understand pexpect.match, unfortunately!
+# pylint:disable=maybe-no-member
 
 class testWalkthrough( unittest.TestCase ):
+    "Test Mininet walkthrough"
 
     prompt = 'mininet>'
 
+    @staticmethod
+    def setup():
+        "Be paranoid and run cleanup() before each test"
+        cleanup()
+
     # PART 1
     def testHelp( self ):
         "Check the usage message"
@@ -31,19 +44,24 @@ class testWalkthrough( unittest.TestCase ):
 
     def testWireshark( self ):
         "Use tshark to test the of dissector"
+        # Satisfy pylint
+        assert self
         if StrictVersion( tsharkVersion() ) < StrictVersion( '1.12.0' ):
             tshark = pexpect.spawn( 'tshark -i lo -R of' )
         else:
             tshark = pexpect.spawn( 'tshark -i lo -Y openflow_v1' )
-        tshark.expect( [ 'Capturing on lo', "Capturing on 'Loopback'" ] )
+        tshark.expect( [ 'Capturing on lo', "Capturing on 'Loopback" ] )
         mn = pexpect.spawn( 'mn --test pingall' )
         mn.expect( '0% dropped' )
         tshark.expect( [ '74 Hello', '74 of_hello', '74 Type: OFPT_HELLO' ] )
         tshark.sendintr()
+        mn.expect( pexpect.EOF )
+        tshark.expect( 'aptured' )  # 'xx packets captured'
+        tshark.expect( pexpect.EOF )
 
     def testBasic( self ):
         "Test basic CLI commands (help, nodes, net, dump)"
-        p = pexpect.spawn( 'mn' )
+        p = pexpect.spawn( 'mn -w' )
         p.expect( self.prompt )
         # help command
         p.sendline( 'help' )
@@ -51,13 +69,13 @@ class testWalkthrough( unittest.TestCase ):
         self.assertEqual( index, 0, 'No output for "help" command')
         # nodes command
         p.sendline( 'nodes' )
-        p.expect( '([chs]\d ?){4}' )
+        p.expect( r'([chs]\d ?){4}' )
         nodes = p.match.group( 0 ).split()
         self.assertEqual( len( nodes ), 4, 'No nodes in "nodes" command')
         p.expect( self.prompt )
         # net command
         p.sendline( 'net' )
-        expected = [ x for x in nodes ]
+        expected = list( nodes )
         while len( expected ) > 0:
             index = p.expect( expected )
             node = p.match.group( 0 )
@@ -67,29 +85,33 @@ class testWalkthrough( unittest.TestCase ):
         p.expect( self.prompt )
         # dump command
         p.sendline( 'dump' )
-        expected = [ '<\w+ (%s)' % n for n in nodes ]
+        expected = [ r'<\w+ (%s)' % n for n in nodes ]
         actual = []
         for _ in nodes:
             index = p.expect( expected )
             node = p.match.group( 1 )
             actual.append( node )
             p.expect( '\n' )
-        self.assertEqual( actual.sort(), nodes.sort(), '"nodes" and "dump" differ' )
+        self.assertEqual( actual.sort(), nodes.sort(),
+                          '"nodes" and "dump" differ' )
         p.expect( self.prompt )
         p.sendline( 'exit' )
         p.wait()
 
     def testHostCommands( self ):
         "Test ifconfig and ps on h1 and s1"
-        p = pexpect.spawn( 'mn' )
+        p = pexpect.spawn( 'mn -w' )
         p.expect( self.prompt )
-        interfaces = [ 'h1-eth0', 's1-eth1', '[^-]eth0', 'lo', self.prompt ]
+        # Third pattern is a local interface beginning with 'eth' or 'en'
+        interfaces = [ r'h1-eth0[:\s]', r's1-eth1[:\s]',
+                       r'[^-](eth|en)\w*\d[:\s]', r'lo[:\s]',
+                       self.prompt ]
         # h1 ifconfig
         p.sendline( 'h1 ifconfig -a' )
         ifcount = 0
         while True:
             index = p.expect( interfaces )
-            if index == 0 or index == 3:
+            if index in (0, 3):
                 ifcount += 1
             elif index == 1:
                 self.fail( 's1 interface displayed in "h1 ifconfig"' )
@@ -105,11 +127,11 @@ class testWalkthrough( unittest.TestCase ):
             index = p.expect( interfaces )
             if index == 0:
                 self.fail( 'h1 interface displayed in "s1 ifconfig"' )
-            elif index == 1 or index == 2 or index == 3:
+            elif index in (1, 2, 3):
                 ifcount += 1
             else:
                 break
-        self.assertEqual( ifcount, 3, 'Missing interfaces on s1')
+        self.assertTrue( ifcount >= 3, 'Missing interfaces on s1')
         # h1 ps
         p.sendline( "h1 ps -a | egrep -v 'ps|grep'" )
         p.expect( self.prompt )
@@ -118,16 +140,19 @@ class testWalkthrough( unittest.TestCase ):
         p.sendline( "s1 ps -a | egrep -v 'ps|grep'" )
         p.expect( self.prompt )
         s1Output = p.before
-        # strip command from ps output
-        h1Output = h1Output.split( '\n', 1 )[ 1 ]
-        s1Output = s1Output.split( '\n', 1 )[ 1 ]
-        self.assertEqual( h1Output, s1Output, 'h1 and s1 "ps" output differs')
+        # strip command from ps output and compute diffs
+        h1Output = h1Output.split( '\n' )[ 1: ]
+        s1Output = s1Output.split( '\n' )[ 1: ]
+        diffs = set( h1Output ).difference( set( s1Output ) )
+        # allow up to two diffs to account for daemons, etc.
+        self.assertTrue( len( diffs ) <= 2,
+                         'h1 and s1 "ps" output differ too much: %s' % diffs )
         p.sendline( 'exit' )
         p.wait()
 
     def testConnectivity( self ):
         "Test ping and pingall"
-        p = pexpect.spawn( 'mn' )
+        p = pexpect.spawn( 'mn -w' )
         p.expect( self.prompt )
         p.sendline( 'h1 ping -c 1 h2' )
         p.expect( '1 packets transmitted, 1 received' )
@@ -140,9 +165,20 @@ class testWalkthrough( unittest.TestCase ):
 
     def testSimpleHTTP( self ):
         "Start an HTTP server on h1 and wget from h2"
-        p = pexpect.spawn( 'mn' )
+        if 'Python 2' in quietRun( 'python --version' ):
+            httpserver = 'SimpleHTTPServer'
+        else:
+            httpserver = 'http.server'
+        p = pexpect.spawn( 'mn -w', logfile=stdout )
         p.expect( self.prompt )
-        p.sendline( 'h1 python -m SimpleHTTPServer 80 &' )
+        p.sendline( 'h1 python -m %s 80 >& /dev/null &' % httpserver )
+        p.expect( self.prompt )
+        # The walkthrough doesn't specify a delay here, and
+        # we also don't read the output (also a possible problem),
+        # but for now let's wait a number of seconds to make
+        # it less likely to fail due to the race condition.
+        p.sendline( 'px from mininet.util import waitListening;'
+                    'waitListening(h1, port=80, timeout=30)' )
         p.expect( self.prompt )
         p.sendline( ' h2 wget -O - h1' )
         p.expect( '200 OK' )
@@ -161,7 +197,7 @@ class testWalkthrough( unittest.TestCase ):
         p.expect( pexpect.EOF )
         # test iperf
         p = pexpect.spawn( 'mn --test iperf' )
-        p.expect( "Results: \['([\d\.]+) .bits/sec'," )
+        p.expect( r"Results: \['([\d\.]+) .bits/sec'," )
         bw = float( p.match.group( 1 ) )
         self.assertTrue( bw > 0 )
         p.expect( pexpect.EOF )
@@ -170,7 +206,7 @@ class testWalkthrough( unittest.TestCase ):
         "Test pingall on single,3 and linear,4 topos"
         # testing single,3
         p = pexpect.spawn( 'mn --test pingall --topo single,3' )
-        p.expect( '(\d+)/(\d+) received')
+        p.expect( r'(\d+)/(\d+) received')
         received = int( p.match.group( 1 ) )
         sent = int( p.match.group( 2 ) )
         self.assertEqual( sent, 6, 'Wrong number of pings sent in single,3' )
@@ -178,7 +214,7 @@ class testWalkthrough( unittest.TestCase ):
         p.expect( pexpect.EOF )
         # testing linear,4
         p = pexpect.spawn( 'mn --test pingall --topo linear,4' )
-        p.expect( '(\d+)/(\d+) received')
+        p.expect( r'(\d+)/(\d+) received')
         received = int( p.match.group( 1 ) )
         sent = int( p.match.group( 2 ) )
         self.assertEqual( sent, 12, 'Wrong number of pings sent in linear,4' )
@@ -187,21 +223,24 @@ class testWalkthrough( unittest.TestCase ):
 
     def testLinkChange( self ):
         "Test TCLink bw and delay"
-        p = pexpect.spawn( 'mn --link tc,bw=10,delay=10ms' )
+        p = pexpect.spawn( 'mn -w --link tc,bw=10,delay=10ms' )
+        p.expect( self.prompt )
+        p.sendline( 'h1 route && ping -c1 h2' )
         # test bw
         p.expect( self.prompt )
         p.sendline( 'iperf' )
-        p.expect( "Results: \['([\d\.]+) Mbits/sec'," )
+        p.expect( r"Results: \['([\d\.]+) Mbits/sec'," )
         bw = float( p.match.group( 1 ) )
-        self.assertTrue( bw < 10.1, 'Bandwidth > 10 Mb/s')
-        self.assertTrue( bw > 9.0, 'Bandwidth < 9 Mb/s')
+        self.assertTrue( bw < 10.1, 'Bandwidth %.2f >= 10.1 Mb/s' % bw )
+        self.assertTrue( bw > 9.0, 'Bandwidth %.2f <= 9 Mb/s' % bw )
         p.expect( self.prompt )
         # test delay
         p.sendline( 'h1 ping -c 4 h2' )
-        p.expect( 'rtt min/avg/max/mdev = ([\d\.]+)/([\d\.]+)/([\d\.]+)/([\d\.]+) ms' )
+        p.expect( r'rtt min/avg/max/mdev = '
+                  r'([\d\.]+)/([\d\.]+)/([\d\.]+)/([\d\.]+) ms' )
         delay = float( p.match.group( 2 ) )
-        self.assertTrue( delay > 40, 'Delay < 40ms' )
-        self.assertTrue( delay < 45, 'Delay > 40ms' )
+        self.assertTrue( delay >= 40, 'Delay < 40ms' )
+        self.assertTrue( delay <= 50, 'Delay > 50ms' )
         p.expect( self.prompt )
         p.sendline( 'exit' )
         p.wait()
@@ -222,10 +261,13 @@ class testWalkthrough( unittest.TestCase ):
 
     def testCustomTopo( self ):
         "Start Mininet using a custom topo, then run pingall"
+        # Satisfy pylint
+        assert self
         custom = os.path.dirname( os.path.realpath( __file__ ) )
         custom = os.path.join( custom, '../../custom/topo-2sw-2host.py' )
         custom = os.path.normpath( custom )
-        p = pexpect.spawn( 'mn --custom %s --topo mytopo --test pingall' % custom )
+        p = pexpect.spawn(
+            'mn --custom %s --topo mytopo --test pingall' % custom )
         p.expect( '0% dropped' )
         p.expect( pexpect.EOF )
 
@@ -235,15 +277,17 @@ class testWalkthrough( unittest.TestCase ):
         p.expect( self.prompt )
         for i in range( 1, 3 ):
             p.sendline( 'h%d ifconfig' % i )
-            p.expect( 'HWaddr 00:00:00:00:00:0%d' % i )
+            p.expect( r'\s00:00:00:00:00:0%d\s' % i )
             p.expect( self.prompt )
+        p.sendline( 'exit' )
+        p.expect( pexpect.EOF )
 
     def testSwitches( self ):
         "Run iperf test using user and ovsk switches"
         switches = [ 'user', 'ovsk' ]
         for sw in switches:
             p = pexpect.spawn( 'mn --switch %s --test iperf' % sw )
-            p.expect( "Results: \['([\d\.]+) .bits/sec'," )
+            p.expect( r"Results: \['([\d\.]+) .bits/sec'," )
             bw = float( p.match.group( 1 ) )
             self.assertTrue( bw > 0 )
             p.expect( pexpect.EOF )
@@ -251,7 +295,7 @@ class testWalkthrough( unittest.TestCase ):
     def testBenchmark( self ):
         "Run benchmark and verify that it takes less than 2 seconds"
         p = pexpect.spawn( 'mn --test none' )
-        p.expect( 'completed in ([\d\.]+) seconds' )
+        p.expect( r'completed in ([\d\.]+) seconds' )
         time = float( p.match.group( 1 ) )
         self.assertTrue( time < 2, 'Benchmark takes more than 2 seconds' )
 
@@ -259,12 +303,14 @@ class testWalkthrough( unittest.TestCase ):
         "Test running user switch in its own namespace"
         p = pexpect.spawn( 'mn --innamespace --switch user' )
         p.expect( self.prompt )
-        interfaces = [ 'h1-eth0', 's1-eth1', '[^-]eth0', 'lo', self.prompt ]
+        interfaces = [ r'h1-eth0[:\s]', r's1-eth1[:\s]',
+                       r'[^-](eth|en)\w*\d[:\s]', r'lo[:\s]',
+                       self.prompt ]
         p.sendline( 's1 ifconfig -a' )
         ifcount = 0
         while True:
             index = p.expect( interfaces )
-            if index == 1 or index == 3:
+            if index in (1, 3):
                 ifcount += 1
             elif index == 0:
                 self.fail( 'h1 interface displayed in "s1 ifconfig"' )
@@ -275,7 +321,7 @@ class testWalkthrough( unittest.TestCase ):
         self.assertEqual( ifcount, 2, 'Missing interfaces on s1' )
         # verify that all hosts a reachable
         p.sendline( 'pingall' )
-        p.expect( '(\d+)% dropped' )
+        p.expect( r'(\d+)% dropped' )
         dropped = int( p.match.group( 1 ) )
         self.assertEqual( dropped, 0, 'pingall failed')
         p.expect( self.prompt )
@@ -285,7 +331,7 @@ class testWalkthrough( unittest.TestCase ):
     # PART 3
     def testPythonInterpreter( self ):
         "Test py and px by checking IP for h1 and adding h3"
-        p = pexpect.spawn( 'mn' )
+        p = pexpect.spawn( 'mn -w' )
         p.expect( self.prompt )
         # test host IP
         p.sendline( 'py h1.IP()' )
@@ -307,7 +353,7 @@ class testWalkthrough( unittest.TestCase ):
 
     def testLink( self ):
         "Test link CLI command using ping"
-        p = pexpect.spawn( 'mn' )
+        p = pexpect.spawn( 'mn -w' )
         p.expect( self.prompt )
         p.sendline( 'link s1 h1 down' )
         p.expect( self.prompt )
@@ -327,11 +373,15 @@ class testWalkthrough( unittest.TestCase ):
                           'Github is not reachable; cannot download Pox' )
     def testRemoteController( self ):
         "Test Mininet using Pox controller"
+        # Satisfy pylint
+        assert self
         if not os.path.exists( '/tmp/pox' ):
-            p = pexpect.spawn( 'git clone https://github.com/noxrepo/pox.git /tmp/pox' )
+            p = pexpect.spawn(
+                'git clone https://github.com/noxrepo/pox.git /tmp/pox' )
             p.expect( pexpect.EOF )
         pox = pexpect.spawn( '/tmp/pox/pox.py forwarding.l2_learning' )
-        net = pexpect.spawn( 'mn --controller=remote,ip=127.0.0.1,port=6633 --test pingall' )
+        net = pexpect.spawn(
+            'mn --controller=remote,ip=127.0.0.1,port=6633 --test pingall' )
         net.expect( '0% dropped' )
         net.expect( pexpect.EOF )
         pox.sendintr()

mininet/topo.py

@@ -1,5 +1,5 @@
 #!/usr/bin/env python
-'''@package topo
+"""@package topo
 
 Network topology creation.
 
@@ -9,203 +9,293 @@ This package includes code to represent network topologies.
 
 A Topo object can be a topology database for NOX, can represent a physical
 setup for testing, and can even be emulated with the Mininet package.
-'''
+"""
 
 from mininet.util import irange, natural, naturalSeq
 
+# pylint: disable=too-many-arguments
+
+
 class MultiGraph( object ):
-    "Utility class to track nodes and edges - replaces networkx.Graph"
+    "Utility class to track nodes and edges - replaces networkx.MultiGraph"
 
     def __init__( self ):
-        self.data = {}
+        self.node = {}
+        self.edge = {}
 
-    def add_node( self, node ):
-        "Add node to graph"
-        self.data.setdefault( node, [] )
+    def add_node( self, node, attr_dict=None, **attrs):
+        """Add node to graph
+           attr_dict: attribute dict (optional)
+           attrs: more attributes (optional)
+           warning: updates attr_dict with attrs"""
+        attr_dict = {} if attr_dict is None else attr_dict
+        attr_dict.update( attrs )
+        self.node[ node ] = attr_dict
 
-    def add_edge( self, src, dest ):
-        "Add edge to graph"
-        src, dest = sorted( ( src, dest ) )
-        self.add_node( src )
-        self.add_node( dest )
-        self.data[ src ].append( dest )
+    def add_edge( self, src, dst, key=None, attr_dict=None, **attrs ):
+        """Add edge to graph
+           key: optional key
+           attr_dict: optional attribute dict
+           attrs: more attributes
+           warning: updates attr_dict with attrs"""
+        attr_dict = {} if attr_dict is None else attr_dict
+        attr_dict.update( attrs )
+        self.node.setdefault( src, {} )
+        self.node.setdefault( dst, {} )
+        self.edge.setdefault( src, {} )
+        self.edge.setdefault( dst, {} )
+        self.edge[ src ].setdefault( dst, {} )
+        entry = self.edge[ dst ][ src ] = self.edge[ src ][ dst ]
+        # If no key, pick next ordinal number
+        if key is None:
+            keys = [ k for k in entry.keys() if isinstance( k, int ) ]
+            key = max( [ 0 ] + keys ) + 1
+        entry[ key ] = attr_dict
+        return key
 
-    def nodes( self ):
-        "Return list of graph nodes"
-        return self.data.keys()
+    def nodes( self, data=False):
+        """Return list of graph nodes
+           data: return list of ( node, attrs)"""
+        return self.node.items() if data else self.node.keys()
 
-    def edges( self ):
-        "Iterator: return graph edges"
-        for src in self.data.keys():
-            for dest in self.data[ src ]:
-                yield ( src, dest )
+    def edges_iter( self, data=False, keys=False ):
+        "Iterator: return graph edges, optionally with data and keys"
+        for src, entry in self.edge.items():
+            for dst, entrykeys in entry.items():
+                if src > dst:
+                    # Skip duplicate edges
+                    continue
+                for k, attrs in entrykeys.items():
+                    if data:
+                        if keys:
+                            yield( src, dst, k, attrs )
+                        else:
+                            yield( src, dst, attrs )
+                    else:
+                        if keys:
+                            yield( src, dst, k )
+                        else:
+                            yield( src, dst )
+
+    def edges( self, data=False, keys=False ):
+        "Return list of graph edges"
+        return list( self.edges_iter( data=data, keys=keys ) )
 
     def __getitem__( self, node ):
-        "Return link dict for the given node"
-        return self.data[node]
+        "Return link dict for given src node"
+        return self.edge[ node ]
+
+    def __len__( self ):
+        "Return the number of nodes"
+        return len( self.node )
+
+    def convertTo( self, cls, data=False, keys=False ):
+        """Convert to a new object of networkx.MultiGraph-like class cls
+           data: include node and edge data
+           keys: include edge keys as well as edge data"""
+        g = cls()
+        g.add_nodes_from( self.nodes( data=data ) )
+        g.add_edges_from( self.edges( data=( data or keys ), keys=keys ) )
+        return g
 
 
-class Topo(object):
+class Topo( object ):
     "Data center network representation for structured multi-trees."
 
-    def __init__(self, *args, **params):
-        """Topo object. 
+    def __init__( self, *args, **params ):
+        """Topo object.
            Optional named parameters:
            hinfo: default host options
            sopts: default switch options
            lopts: default link options
            calls build()"""
         self.g = MultiGraph()
-        self.node_info = {}
-        self.link_info = {}  # (src, dst) tuples hash to EdgeInfo objects
         self.hopts = params.pop( 'hopts', {} )
         self.sopts = params.pop( 'sopts', {} )
         self.lopts = params.pop( 'lopts', {} )
-        self.ports = {}  # ports[src][dst] is port on src that connects to dst
+        # ports[src][dst][sport] is port on dst that connects to src
+        self.ports = {}
         self.build( *args, **params )
 
     def build( self, *args, **params ):
         "Override this method to build your topology."
         pass
 
-    def addNode(self, name, **opts):
+    def addNode( self, name, **opts ):
         """Add Node to graph.
            name: name
            opts: node options
            returns: node name"""
-        self.g.add_node(name)
-        self.node_info[name] = opts
+        self.g.add_node( name, **opts )
         return name
 
-    def addHost(self, name, **opts):
+    def addHost( self, name, **opts ):
         """Convenience method: Add host to graph.
            name: host name
            opts: host options
            returns: host name"""
         if not opts and self.hopts:
             opts = self.hopts
-        return self.addNode(name, **opts)
+        return self.addNode( name, **opts )
 
-    def addSwitch(self, name, **opts):
+    def addSwitch( self, name, **opts ):
         """Convenience method: Add switch to graph.
            name: switch name
            opts: switch options
            returns: switch name"""
         if not opts and self.sopts:
             opts = self.sopts
-        result = self.addNode(name, isSwitch=True, **opts)
+        result = self.addNode( name, isSwitch=True, **opts )
         return result
 
-    def addLink(self, node1, node2, port1=None, port2=None,
-                **opts):
+    def addLink( self, node1, node2, port1=None, port2=None,
+                 key=None, **opts ):
         """node1, node2: nodes to link together
            port1, port2: ports (optional)
            opts: link options (optional)
            returns: link info key"""
         if not opts and self.lopts:
             opts = self.lopts
-        self.addPort(node1, node2, port1, port2)
-        key = tuple(self.sorted([node1, node2]))
-        self.link_info[key] = opts
-        self.g.add_edge(*key)
-        return key
+        port1, port2 = self.addPort( node1, node2, port1, port2 )
+        opts = dict( opts )
+        opts.update( node1=node1, node2=node2, port1=port1, port2=port2 )
+        return self.g.add_edge(node1, node2, key, opts )
 
-    def addPort(self, src, dst, sport=None, dport=None):
-        '''Generate port mapping for new edge.
-        @param src source switch name
-        @param dst destination switch name
-        '''
-        self.ports.setdefault(src, {})
-        self.ports.setdefault(dst, {})
-        # New port: number of outlinks + base
-        src_base = 1 if self.isSwitch(src) else 0
-        dst_base = 1 if self.isSwitch(dst) else 0
-        if sport is None:
-            sport = len(self.ports[src]) + src_base
-        if dport is None:
-            dport = len(self.ports[dst]) + dst_base
-        self.ports[src][dst] = sport
-        self.ports[dst][src] = dport
-
-    def nodes(self, sort=True):
+    def nodes( self, sort=True ):
         "Return nodes in graph"
         if sort:
             return self.sorted( self.g.nodes() )
         else:
             return self.g.nodes()
 
-    def isSwitch(self, n):
-        '''Returns true if node is a switch.'''
-        info = self.node_info[n]
-        return info and info.get('isSwitch', False)
+    def isSwitch( self, n ):
+        "Returns true if node is a switch."
+        return self.g.node[ n ].get( 'isSwitch', False )
 
-    def switches(self, sort=True):
-        '''Return switches.
-        sort: sort switches alphabetically
-        @return dpids list of dpids
-        '''
-        return [n for n in self.nodes(sort) if self.isSwitch(n)]
+    def switches( self, sort=True ):
+        """Return switches.
+           sort: sort switches alphabetically
+           returns: dpids list of dpids"""
+        return [ n for n in self.nodes( sort ) if self.isSwitch( n ) ]
 
-    def hosts(self, sort=True):
-        '''Return hosts.
-        sort: sort hosts alphabetically
-        @return dpids list of dpids
-        '''
-        return [n for n in self.nodes(sort) if not self.isSwitch(n)]
+    def hosts( self, sort=True ):
+        """Return hosts.
+           sort: sort hosts alphabetically
+           returns: list of hosts"""
+        return [ n for n in self.nodes( sort ) if not self.isSwitch( n ) ]
 
-    def links(self, sort=True):
-        '''Return links.
-        sort: sort links alphabetically
-        @return links list of name pairs
-        '''
+    def iterLinks( self, withKeys=False, withInfo=False ):
+        """Return links (iterator)
+           withKeys: return link keys
+           withInfo: return link info
+           returns: list of ( src, dst [,key, info ] )"""
+        for _src, _dst, key, info in self.g.edges_iter( data=True, keys=True ):
+            node1, node2 = info[ 'node1' ], info[ 'node2' ]
+            if withKeys:
+                if withInfo:
+                    yield( node1, node2, key, info )
+                else:
+                    yield( node1, node2, key )
+            else:
+                if withInfo:
+                    yield( node1, node2, info )
+                else:
+                    yield( node1, node2 )
+
+    def links( self, sort=False, withKeys=False, withInfo=False ):
+        """Return links
+           sort: sort links alphabetically, preserving (src, dst) order
+           withKeys: return link keys
+           withInfo: return link info
+           returns: list of ( src, dst [,key, info ] )"""
+        links = list( self.iterLinks( withKeys, withInfo ) )
         if not sort:
-            return self.g.edges()
-        else:
-            links = [tuple(self.sorted(e)) for e in self.g.edges()]
-            return sorted( links, key=naturalSeq )
+            return links
+        # Ignore info when sorting
+        tupleSize = 3 if withKeys else 2
+        return sorted( links, key=( lambda l: naturalSeq( l[ :tupleSize ] ) ) )
 
-    def port(self, src, dst):
-        '''Get port number.
+    # This legacy port management mechanism is clunky and will probably
+    # be removed at some point.
 
-        @param src source switch name
-        @param dst destination switch name
-        @return tuple (src_port, dst_port):
-            src_port: port on source switch leading to the destination switch
-            dst_port: port on destination switch leading to the source switch
-        '''
-        if src in self.ports and dst in self.ports[src]:
-            assert dst in self.ports and src in self.ports[dst]
-            return self.ports[src][dst], self.ports[dst][src]
+    def addPort( self, src, dst, sport=None, dport=None ):
+        """Generate port mapping for new edge.
+            src: source switch name
+            dst: destination switch name"""
+        # Initialize if necessary
+        ports = self.ports
+        ports.setdefault( src, {} )
+        ports.setdefault( dst, {} )
+        # New port: number of outlinks + base
+        if sport is None:
+            src_base = 1 if self.isSwitch( src ) else 0
+            sport = len( ports[ src ] ) + src_base
+        if dport is None:
+            dst_base = 1 if self.isSwitch( dst ) else 0
+            dport = len( ports[ dst ] ) + dst_base
+        ports[ src ][ sport ] = ( dst, dport )
+        ports[ dst ][ dport ] = ( src, sport )
+        return sport, dport
 
-    def linkInfo( self, src, dst ):
-        "Return link metadata"
-        src, dst = self.sorted([src, dst])
-        return self.link_info[(src, dst)]
+    def port( self, src, dst ):
+        """Get port numbers.
+            src: source switch name
+            dst: destination switch name
+            sport: optional source port (otherwise use lowest src port)
+            returns: tuple (sport, dport), where
+                sport = port on source switch leading to the destination switch
+                dport = port on destination switch leading to the source switch
+            Note that you can also look up ports using linkInfo()"""
+        # A bit ugly and slow vs. single-link implementation ;-(
+        ports = [ ( sport, entry[ 1 ] )
+                  for sport, entry in self.ports[ src ].items()
+                  if entry[ 0 ] == dst ]
+        return ports if len( ports ) != 1 else ports[ 0 ]
 
-    def setlinkInfo( self, src, dst, info ):
-        "Set link metadata"
-        src, dst = self.sorted([src, dst])
-        self.link_info[(src, dst)] = info
+    def _linkEntry( self, src, dst, key=None ):
+        "Helper function: return link entry and key"
+        entry = self.g[ src ][ dst ]
+        if key is None:
+            key = min( entry )
+        return entry, key
+
+    def linkInfo( self, src, dst, key=None ):
+        "Return link metadata dict"
+        entry, key = self._linkEntry( src, dst, key )
+        return entry[ key ]
+
+    def setlinkInfo( self, src, dst, info, key=None ):
+        "Set link metadata dict"
+        entry, key = self._linkEntry( src, dst, key )
+        entry[ key ] = info
 
     def nodeInfo( self, name ):
         "Return metadata (dict) for node"
-        info = self.node_info[ name ]
-        return info if info is not None else {}
+        return self.g.node[ name ]
 
     def setNodeInfo( self, name, info ):
         "Set metadata (dict) for node"
-        self.node_info[ name ] = info
+        self.g.node[ name ] = info
+
+    def convertTo( self, cls, data=True, keys=True ):
+        """Convert to a new object of networkx.MultiGraph-like class cls
+           data: include node and edge data (default True)
+           keys: include edge keys as well as edge data (default True)"""
+        return self.g.convertTo( cls, data=data, keys=keys )
 
     @staticmethod
     def sorted( items ):
         "Items sorted in natural (i.e. alphabetical) order"
-        return sorted(items, key=natural)
+        return sorted( items, key=natural )
 
 
+# Our idiom defines additional parameters in build(param...)
+# pylint: disable=arguments-differ
+
 class SingleSwitchTopo( Topo ):
     "Single switch connected to k hosts."
 
-    def build( self, k=2, **opts ):
+    def build( self, k=2, **_opts ):
         "k: number of hosts"
         self.k = k
         switch = self.addSwitch( 's1' )
@@ -217,7 +307,8 @@ class SingleSwitchTopo( Topo ):
 class SingleSwitchReversedTopo( Topo ):
     """Single switch connected to k hosts, with reversed ports.
        The lowest-numbered host is connected to the highest-numbered port.
-       Useful to verify that Mininet properly handles custom port numberings."""
+       Useful to verify that Mininet properly handles custom port
+       numberings."""
 
     def build( self, k=2 ):
         "k: number of hosts"
@@ -228,19 +319,28 @@ class SingleSwitchReversedTopo( Topo ):
             self.addLink( host, switch,
                           port1=0, port2=( k - h + 1 ) )
 
+
+class MinimalTopo( SingleSwitchTopo ):
+    "Minimal topology with two hosts and one switch"
+    def build( self ):
+        return SingleSwitchTopo.build( self, k=2 )
+
+
 class LinearTopo( Topo ):
     "Linear topology of k switches, with n hosts per switch."
 
-    def build( self, k=2, n=1, **opts):
+    def build( self, k=2, n=1, **_opts):
         """k: number of switches
            n: number of hosts per switch"""
         self.k = k
         self.n = n
 
         if n == 1:
-            genHostName = lambda i, j: 'h%s' % i
+            def genHostName( i, _j ):
+                return 'h%s' % i
         else:
-            genHostName = lambda i, j: 'h%ss%d' % ( j, i )
+            def genHostName( i, j ):
+                return 'h%ss%d' % ( j, i )
 
         lastSwitch = None
         for i in irange( 1, k ):
@@ -254,3 +354,5 @@ class LinearTopo( Topo ):
             if lastSwitch:
                 self.addLink( switch, lastSwitch )
             lastSwitch = switch
+
+# pylint: enable=arguments-differ

mininet/topolib.py

@@ -3,6 +3,9 @@
 from mininet.topo import Topo
 from mininet.net import Mininet
 
+# The build() method is expected to do this:
+# pylint: disable=arguments-differ
+
 class TreeTopo( Topo ):
     "Topology for a tree network with a given depth and fanout."
 
@@ -41,11 +44,21 @@ class TorusTopo( Topo ):
        with the default controller or any Ethernet bridge
        without STP turned on! It can be used with STP, e.g.:
        # mn --topo torus,3,3 --switch lxbr,stp=1 --test pingall"""
-    
-    def build( self, x, y ):
+
+    def build( self, x, y, n=1 ):
+        """x: dimension of torus in x-direction
+           y: dimension of torus in y-direction
+           n: number of hosts per switch"""
         if x < 3 or y < 3:
             raise Exception( 'Please use 3x3 or greater for compatibility '
-                            'with 2.1' )
+                             'with 2.1' )
+        if n == 1:
+            def genHostName( loc, _k ):
+                return 'h%s' % ( loc )
+        else:
+            def genHostName( loc, k ):
+                return 'h%sx%d' % ( loc, k )
+
         hosts, switches, dpid = {}, {}, 0
         # Create and wire interior
         for i in range( 0, x ):
@@ -53,9 +66,12 @@ class TorusTopo( Topo ):
                 loc = '%dx%d' % ( i + 1, j + 1 )
                 # dpid cannot be zero for OVS
                 dpid = ( i + 1 ) * 256 + ( j + 1 )
-                switch = switches[ i, j ] = self.addSwitch( 's' + loc, dpid='%016x' % dpid )
-                host = hosts[ i, j ] = self.addHost( 'h' + loc )
-                self.addLink( host, switch )
+                switch = switches[ i, j ] = self.addSwitch(
+                    's' + loc, dpid='%x' % dpid )
+                for k in range( 0, n ):
+                    host = hosts[ i, j, k ] = self.addHost(
+                        genHostName( loc, k + 1 ) )
+                    self.addLink( host, switch )
         # Connect switches
         for i in range( 0, x ):
             for j in range( 0, y ):
@@ -65,5 +81,4 @@ class TorusTopo( Topo ):
                 self.addLink( sw1, sw2 )
                 self.addLink( sw1, sw3 )
 
-    
-
+# pylint: enable=arguments-differ

mininet/util.py

@@ -1,16 +1,86 @@
 "Utility functions for Mininet."
 
-from mininet.log import output, info, error, warn, debug
+import codecs
+import os
+import re
+import sys
 
-from time import sleep
+from collections import namedtuple
+from fcntl import fcntl, F_GETFL, F_SETFL
+from functools import partial
+from os import O_NONBLOCK
 from resource import getrlimit, setrlimit, RLIMIT_NPROC, RLIMIT_NOFILE
 from select import poll, POLLIN, POLLHUP
 from subprocess import call, check_call, Popen, PIPE, STDOUT
-import re
-from fcntl import fcntl, F_GETFL, F_SETFL
-from os import O_NONBLOCK
-import os
-from functools import partial
+from sys import exit  # pylint: disable=redefined-builtin
+from time import sleep
+
+from mininet.log import output, info, error, warn, debug
+
+# pylint: disable=too-many-arguments
+
+
+# Python 2/3 compatibility
+
+Python3 = sys.version_info[0] == 3
+BaseString = str if Python3 else getattr( str, '__base__' )
+Encoding = 'utf-8' if Python3 else None
+class NullCodec( object ):
+    "Null codec for Python 2"
+    @staticmethod
+    def decode( buf ):
+        "Null decode"
+        return buf
+
+    @staticmethod
+    def encode( buf ):
+        "Null encode"
+        return buf
+
+
+if Python3:
+    def decode( buf ):
+        "Decode buffer for Python 3"
+        return buf.decode( Encoding )
+
+    def encode( buf ):
+        "Encode buffer for Python 3"
+        return buf.encode( Encoding )
+    getincrementaldecoder = codecs.getincrementaldecoder( Encoding )
+
+else:
+    decode, encode = NullCodec.decode, NullCodec.encode
+
+    def getincrementaldecoder():
+        "Return null codec for Python 2"
+        return NullCodec
+
+try:
+    import packaging.version  # replacement for distutils.version
+    StrictVersion = packaging.version.parse
+except ImportError:  # python2.7 lacks ModuleNotFoundError
+    import distutils.version  # pylint: disable=deprecated-module
+    StrictVersion = distutils.version.StrictVersion
+
+try:
+    oldpexpect = None
+    import pexpect as oldpexpect  # pylint: disable=import-error
+
+    class Pexpect( object ):
+        "Custom pexpect that is compatible with str"
+        @staticmethod
+        def spawn( *args, **kwargs):
+            "pexpect.spawn that is compatible with str"
+            if Python3 and 'encoding' not in kwargs:
+                kwargs.update( encoding='utf-8'  )
+            return oldpexpect.spawn( *args, **kwargs )
+
+        def __getattr__( self, name ):
+            return getattr( oldpexpect, name )
+    pexpect = Pexpect()
+except ImportError:
+    pass
+
 
 # Command execution support
 
@@ -25,20 +95,21 @@ def checkRun( cmd ):
     return check_call( cmd.split( ' ' ) )
 
 # pylint doesn't understand explicit type checking
-# pylint: disable-msg=E1103
+# pylint: disable=maybe-no-member
 
 def oldQuietRun( *cmd ):
     """Run a command, routing stderr to stdout, and return the output.
        cmd: list of command params"""
     if len( cmd ) == 1:
         cmd = cmd[ 0 ]
-        if isinstance( cmd, str ):
+        if isinstance( cmd, BaseString ):
             cmd = cmd.split( ' ' )
-    popen = Popen( cmd, stdout=PIPE, stderr=STDOUT )
+    out = ''
+    popen = Popen(  # pylint: disable=consider-using-with
+        cmd, stdout=PIPE, stderr=STDOUT )
     # We can't use Popen.communicate() because it uses
     # select(), which can't handle
     # high file descriptor numbers! poll() can, however.
-    out = ''
     readable = poll()
     readable.register( popen.stdout )
     while True:
@@ -56,6 +127,9 @@ def oldQuietRun( *cmd ):
 # This is a bit complicated, but it enables us to
 # monitor command output as it is happening
 
+CmdResult = namedtuple( 'CmdResult', 'out err ret' )
+
+# pylint: disable=too-many-branches,too-many-statements
 def errRun( *cmd, **kwargs ):
     """Run a command and return stdout, stderr and return code
        cmd: string or list of command and args
@@ -72,40 +146,60 @@ def errRun( *cmd, **kwargs ):
     if len( cmd ) == 1:
         cmd = cmd[ 0 ]
     # Allow passing in a list or a string
-    if isinstance( cmd, str ) and not shell:
+    if isinstance( cmd, BaseString ) and not shell:
         cmd = cmd.split( ' ' )
         cmd = [ str( arg ) for arg in cmd ]
     elif isinstance( cmd, list ) and shell:
         cmd = " ".join( arg for arg in cmd )
+    debug( '*** errRun:', cmd, '\n' )
+    # pylint: disable=consider-using-with
     popen = Popen( cmd, stdout=PIPE, stderr=stderr, shell=shell )
     # We use poll() because select() doesn't work with large fd numbers,
     # and thus communicate() doesn't work either
     out, err = '', ''
     poller = poll()
     poller.register( popen.stdout, POLLIN )
-    fdtofile = { popen.stdout.fileno(): popen.stdout }
+    fdToFile = { popen.stdout.fileno(): popen.stdout }
+    fdToDecoder = { popen.stdout.fileno(): getincrementaldecoder() }
     outDone, errDone = False, True
     if popen.stderr:
-        fdtofile[ popen.stderr.fileno() ] = popen.stderr
+        fdToFile[ popen.stderr.fileno() ] = popen.stderr
+        fdToDecoder[ popen.stderr.fileno() ] = getincrementaldecoder()
         poller.register( popen.stderr, POLLIN )
         errDone = False
     while not outDone or not errDone:
         readable = poller.poll()
-        for fd, _event in readable:
-            f = fdtofile[ fd ]
-            data = f.read( 1024 )
-            if echo:
-                output( data )
-            if f == popen.stdout:
-                out += data
-                if data == '':
+        for fd, event in readable:
+            f = fdToFile[ fd ]
+            decoder = fdToDecoder[ fd ]
+            if event & ( POLLIN | POLLHUP ):
+                data = decoder.decode( f.read( 1024 ) )
+                if echo:
+                    output( data )
+                if f == popen.stdout:
+                    out += data
+                    if data == '':
+                        outDone = True
+                elif f == popen.stderr:
+                    err += data
+                    if data == '':
+                        errDone = True
+            else:  # something unexpected
+                if f == popen.stdout:
                     outDone = True
-            elif f == popen.stderr:
-                err += data
-                if data == '':
+                elif f == popen.stderr:
                     errDone = True
+                poller.unregister( fd )
+
     returncode = popen.wait()
-    return out, err, returncode
+    # Python 3 complains if we don't explicitly close these
+    popen.stdout.close()
+    if stderr == PIPE:
+        popen.stderr.close()
+    debug( out, err, returncode )
+    return CmdResult( out, err, returncode )
+
+# pylint: enable=too-many-branches
 
 def errFail( *cmd, **kwargs ):
     "Run a command using errRun and raise exception on nonzero exit"
@@ -113,27 +207,31 @@ def errFail( *cmd, **kwargs ):
     if ret:
         raise Exception( "errFail: %s failed with return code %s: %s"
                          % ( cmd, ret, err ) )
-    return out, err, ret
+    return CmdResult( out, err, ret )
 
 def quietRun( cmd, **kwargs ):
     "Run a command and return merged stdout and stderr"
-    return errRun( cmd, stderr=STDOUT, **kwargs )[ 0 ]
+    return errRun( cmd, stderr=STDOUT, **kwargs ).out
 
-# pylint: enable-msg=E1103
-# pylint: disable-msg=E1101
+def which(cmd, **kwargs ):
+    "Run a command and return merged stdout and stderr"
+    out, _, ret = errRun( ["which", cmd], stderr=STDOUT, **kwargs )
+    return out.rstrip() if ret == 0 else None
+
+# pylint: enable=maybe-no-member
 
 def isShellBuiltin( cmd ):
     "Return True if cmd is a bash builtin."
     if isShellBuiltin.builtIns is None:
-        isShellBuiltin.builtIns = quietRun( 'bash -c enable' )
+        isShellBuiltin.builtIns = set(quietRun( 'bash -c enable' ).split())
     space = cmd.find( ' ' )
     if space > 0:
         cmd = cmd[ :space]
     return cmd in isShellBuiltin.builtIns
 
+
 isShellBuiltin.builtIns = None
 
-# pylint: enable-msg=E1101
 
 # Interface management
 #
@@ -148,27 +246,41 @@ isShellBuiltin.builtIns = None
 # live in the root namespace and thus do not have to be
 # explicitly moved.
 
-def makeIntfPair( intf1, intf2, addr1=None, addr2=None, run=quietRun ):
-    """Make a veth pair connecting intf1 and intf2.
-       intf1: string, interface
-       intf2: string, interface
-       node: node to run on or None (default)
-       returns: ip link add result"""
-    # Delete any old interfaces with the same names
-    run( 'ip link del ' + intf1 )
-    run( 'ip link del ' + intf2 )
+def makeIntfPair( intf1, intf2, addr1=None, addr2=None, node1=None, node2=None,
+                  deleteIntfs=True, runCmd=None ):
+    """Make a veth pair connnecting new interfaces intf1 and intf2
+       intf1: name for interface 1
+       intf2: name for interface 2
+       addr1: MAC address for interface 1 (optional)
+       addr2: MAC address for interface 2 (optional)
+       node1: home node for interface 1 (optional)
+       node2: home node for interface 2 (optional)
+       deleteIntfs: delete intfs before creating them
+       runCmd: function to run shell commands (quietRun)
+       raises Exception on failure"""
+    if not runCmd:
+        runCmd = quietRun if not node1 else node1.cmd
+        runCmd2 = quietRun if not node2 else node2.cmd
+    if deleteIntfs:
+        # Delete any old interfaces with the same names
+        runCmd( 'ip link del ' + intf1 )
+        runCmd2( 'ip link del ' + intf2 )
     # Create new pair
+    netns = 1 if not node2 else node2.pid
     if addr1 is None and addr2 is None:
-        cmd = 'ip link add name ' + intf1 + ' type veth peer name ' + intf2
+        cmdOutput = runCmd( 'ip link add name %s '
+                            'type veth peer name %s '
+                            'netns %s' % ( intf1, intf2, netns ) )
     else:
-        cmd = ( 'ip link add name ' + intf1 + ' address ' + addr1 +
-                ' type veth peer name ' + intf2 + ' address ' + addr2 )
-    cmdOutput = run( cmd )
-    if cmdOutput == '':
-        return True
-    else:
-        error( "Error creating interface pair: %s " % cmdOutput )
-        return False
+        cmdOutput = runCmd( 'ip link add name %s '
+                            'address %s '
+                            'type veth peer name %s '
+                            'address %s '
+                            'netns %s' %
+                            (  intf1, addr1, intf2, addr2, netns ) )
+    if cmdOutput:
+        raise Exception( "Error creating interface pair (%s,%s): %s " %
+                         ( intf1, intf2, cmdOutput ) )
 
 def retry( retries, delaySecs, fn, *args, **keywords ):
     """Try something several times before giving up.
@@ -202,8 +314,8 @@ def moveIntfNoRetry( intf, dstNode, printError=False ):
         return False
     return True
 
-def moveIntf( intf, dstNode, srcNode=None, printError=True,
-             retries=3, delaySecs=0.001 ):
+def moveIntf( intf, dstNode, printError=True,
+              retries=3, delaySecs=0.001 ):
     """Move interface to node, retrying on failure.
        intf: string, interface
        dstNode: destination Node
@@ -296,8 +408,8 @@ def ipAdd( i, prefixLen=8, ipBaseNum=0x0a000000 ):
 def ipParse( ip ):
     "Parse an IP address and return an unsigned int."
     args = [ int( arg ) for arg in ip.split( '.' ) ]
-    while ( len(args) < 4 ):
-        args.append( 0 )
+    while len(args) < 4:
+        args.insert( len(args) - 1, 0 )
     return ipNum( *args )
 
 def netParse( ipstr ):
@@ -307,7 +419,7 @@ def netParse( ipstr ):
     if '/' in ipstr:
         ip, pf = ipstr.split( '/' )
         prefixLen = int( pf )
-    #if no prefix is specified, set the prefix to 24
+    # if no prefix is specified, set the prefix to 24
     else:
         ip = ipstr
         prefixLen = 24
@@ -350,30 +462,34 @@ def pmonitor(popens, timeoutms=500, readline=True,
        terminates: when all EOFs received"""
     poller = poll()
     fdToHost = {}
-    for host, popen in popens.iteritems():
+    fdToDecoder = {}
+    for host, popen in popens.items():
         fd = popen.stdout.fileno()
         fdToHost[ fd ] = host
+        fdToDecoder[ fd ] = getincrementaldecoder()
         poller.register( fd, POLLIN )
-        if not readline:
-            # Use non-blocking reads
-            flags = fcntl( fd, F_GETFL )
-            fcntl( fd, F_SETFL, flags | O_NONBLOCK )
+        flags = fcntl( fd, F_GETFL )
+        fcntl( fd, F_SETFL, flags | O_NONBLOCK )
+    # pylint: disable=too-many-nested-blocks
     while popens:
         fds = poller.poll( timeoutms )
         if fds:
             for fd, event in fds:
                 host = fdToHost[ fd ]
+                decoder = fdToDecoder[ fd ]
                 popen = popens[ host ]
-                if event & POLLIN:
-                    if readline:
-                        # Attempt to read a line of output
-                        # This blocks until we receive a newline!
-                        line = popen.stdout.readline()
-                    else:
-                        line = popen.stdout.read( readmax )
-                    yield host, line
-                # Check for EOF
-                elif event & POLLHUP:
+                if event & ( POLLIN | POLLHUP ):
+                    while True:
+                        try:
+                            f = popen.stdout
+                            line = decoder.decode( f.readline() if readline
+                                                   else f.read( readmax ) )
+                        except IOError:
+                            line = ''
+                        if line == '':
+                            break
+                        yield host, line
+                if event & POLLHUP:
                     poller.unregister( fd )
                     del popens[ host ]
         else:
@@ -382,19 +498,19 @@ def pmonitor(popens, timeoutms=500, readline=True,
 # Other stuff we use
 def sysctlTestAndSet( name, limit ):
     "Helper function to set sysctl limits"
-    #convert non-directory names into directory names
+    # convert non-directory names into directory names
     if '/' not in name:
         name = '/proc/sys/' + name.replace( '.', '/' )
-    #read limit
+    # read limit
     with open( name, 'r' ) as readFile:
         oldLimit = readFile.readline()
-        if type( limit ) is int:
-            #compare integer limits before overriding
+        if isinstance( limit, int ):
+            # compare integer limits before overriding
             if int( oldLimit ) < limit:
                 with open( name, 'w' ) as writeFile:
                     writeFile.write( "%d" % limit )
         else:
-            #overwrite non-integer limits
+            # overwrite non-integer limits
             with open( name, 'w' ) as writeFile:
                 writeFile.write( limit )
 
@@ -411,44 +527,54 @@ def fixLimits():
     try:
         rlimitTestAndSet( RLIMIT_NPROC, 8192 )
         rlimitTestAndSet( RLIMIT_NOFILE, 16384 )
-        #Increase open file limit
+        # Increase open file limit
         sysctlTestAndSet( 'fs.file-max', 10000 )
-        #Increase network buffer space
+        # Increase network buffer space
         sysctlTestAndSet( 'net.core.wmem_max', 16777216 )
         sysctlTestAndSet( 'net.core.rmem_max', 16777216 )
         sysctlTestAndSet( 'net.ipv4.tcp_rmem', '10240 87380 16777216' )
         sysctlTestAndSet( 'net.ipv4.tcp_wmem', '10240 87380 16777216' )
         sysctlTestAndSet( 'net.core.netdev_max_backlog', 5000 )
-        #Increase arp cache size
+        # Increase arp cache size
         sysctlTestAndSet( 'net.ipv4.neigh.default.gc_thresh1', 4096 )
         sysctlTestAndSet( 'net.ipv4.neigh.default.gc_thresh2', 8192 )
         sysctlTestAndSet( 'net.ipv4.neigh.default.gc_thresh3', 16384 )
-        #Increase routing table size
+        # Increase routing table size
         sysctlTestAndSet( 'net.ipv4.route.max_size', 32768 )
-        #Increase number of PTYs for nodes
+        # Increase number of PTYs for nodes
         sysctlTestAndSet( 'kernel.pty.max', 20000 )
-    except:
+    # pylint: disable=broad-except
+    except Exception:
         warn( "*** Error setting resource limits. "
               "Mininet's performance may be affected.\n" )
+    # pylint: enable=broad-except
 
-def mountCgroups():
-    "Make sure cgroups file system is mounted"
-    mounts = quietRun( 'cat /proc/mounts' )
-    cgdir = '/sys/fs/cgroup'
-    csdir = cgdir + '/cpuset'
-    if ('cgroup %s' % cgdir not in mounts and
-            'cgroups %s' % cgdir not in mounts):
-        raise Exception( "cgroups not mounted on " + cgdir )
-    if 'cpuset %s' % csdir not in mounts:
-        errRun( 'mkdir -p ' + csdir )
-        errRun( 'mount -t cgroup -ocpuset cpuset ' + csdir )
+def mountCgroups( cgcontrol='cpu cpuacct cpuset' ):
+    """Mount cgroupfs if needed and return cgroup version
+       cgcontrol: cgroup controllers to check ('cpu cpuacct cpuset')
+       Returns: 'cgroup' | 'cgroup2' """
+    # Try to read the cgroup controllers in cgcontrol
+    cglist = cgcontrol.split()
+    paths = ' '.join( '-g ' + c for c in cglist )
+    cmd = 'cgget -n %s /' % paths
+    result = errRun( cmd )
+    # If it failed, mount cgroupfs and retry
+    if result.ret or result.err or any(
+            c not in result.out for c in cglist ):
+        errFail( 'cgroupfs-mount' )
+        result = errRun( cmd )
+        errFail( cmd )
+    # cpu.cfs_period_us is used for cgroup but not cgroup2
+    if 'cpu.cfs_period_us' in result.out:
+        return 'cgroup'
+    return 'cgroup2'
 
 def natural( text ):
     "To sort sanely/alphabetically: sorted( l, key=natural )"
     def num( s ):
         "Convert text segment to int if necessary"
         return int( s ) if s.isdigit() else s
-    return [  num( s ) for s in re.split( r'(\d+)', text ) ]
+    return [  num( s ) for s in re.split( r'(\d+)', str( text ) ) ]
 
 def naturalSeq( t ):
     "Natural sort key function for sequences"
@@ -497,31 +623,54 @@ def splitArgs( argstr ):
         kwargs[ key ] = makeNumeric( val )
     return fn, args, kwargs
 
-def customConstructor( constructors, argStr ):
-    """Return custom constructor based on argStr
-    The args and key/val pairs in argsStr will be automatically applied
-    when the generated constructor is later used.
+def customClass( classes, argStr ):
+    """Return customized class based on argStr
+    The args and key/val pairs in argStr will be automatically applied
+    when the generated class is later used.
     """
-    cname, newargs, kwargs = splitArgs( argStr )
-    constructor = constructors.get( cname, None )
-
-    if not constructor:
+    cname, args, kwargs = splitArgs( argStr )
+    cls = classes.get( cname, None )
+    if not cls:
         raise Exception( "error: %s is unknown - please specify one of %s" %
-                         ( cname, constructors.keys() ) )
+                         ( cname, classes.keys() ) )
+    if not args and not kwargs:
+        return cls
 
-    def customized( name, *args, **params ):
-        "Customized constructor, useful for Node, Link, and other classes"
-        params = params.copy()
-        params.update( kwargs )
-        if not newargs:
-            return constructor( name, *args, **params )
-        if args:
-            warn( 'warning: %s replacing %s with %s\n' % (
-                  constructor, args, newargs ) )
-        return constructor( name, *newargs, **params )
+    return specialClass( cls, append=args, defaults=kwargs )
+
+def specialClass( cls, prepend=None, append=None,
+                  defaults=None, override=None ):
+    """Like functools.partial, but it returns a class
+       prepend: arguments to prepend to argument list
+       append: arguments to append to argument list
+       defaults: default values for keyword arguments
+       override: keyword arguments to override"""
+
+    if prepend is None:
+        prepend = []
+
+    if append is None:
+        append = []
+
+    if defaults is None:
+        defaults = {}
+
+    if override is None:
+        override = {}
+
+    class CustomClass( cls ):
+        "Customized subclass with preset args/params"
+        def __init__( self, *args, **params ):
+            newparams = defaults.copy()
+            newparams.update( params )
+            newparams.update( override )
+            cls.__init__( self, *( list( prepend ) + list( args ) +
+                                   list( append ) ),
+                          **newparams )
+
+    CustomClass.__name__ = '%s%s' % ( cls.__name__, defaults )
+    return CustomClass
 
-    customized.__name__ = 'customConstructor(%s)' % argStr
-    return customized
 
 def buildTopo( topos, topoStr ):
     """Create topology from string with format (object, arg1, arg2,...).
@@ -538,30 +687,55 @@ def ensureRoot():
     Probably we should only sudo when needed as per Big Switch's patch.
     """
     if os.getuid() != 0:
-        print "*** Mininet must run as root."
+        error( '*** Mininet must run as root.\n' )
         exit( 1 )
-    return
 
 def waitListening( client=None, server='127.0.0.1', port=80, timeout=None ):
     """Wait until server is listening on port.
        returns True if server is listening"""
-    run = ( client.cmd if client else
-                partial( quietRun, shell=True ) )
-    if not run( 'which telnet' ):
+    runCmd = ( client.cmd if client else
+               partial( quietRun, shell=True ) )
+    if not runCmd( 'which telnet' ):
         raise Exception('Could not find telnet' )
-    serverIP = server if type( server ) is str else server.IP()
-    cmd = ( 'sh -c "echo A | telnet -e A %s %s"' %
-           ( serverIP, port ) )
+    # pylint: disable=maybe-no-member
+    serverIP = server if isinstance( server, BaseString ) else server.IP()
+    cmd = ( 'echo A | telnet -e A %s %s' % ( serverIP, port ) )
     time = 0
-    while 'Connected' not in run( cmd ):
-        if timeout:
-            print time
-            if time >= timeout:
-                error( 'could not connect to %s on port %d\n'
-                       % ( server, port ) )
-                return False
-        output('waiting for', server,
-               'to listen on port', port, '\n')
+    result = runCmd( cmd )
+    while 'Connected' not in result:
+        if 'No route' in result:
+            rtable = runCmd( 'route' )
+            error( 'no route to %s:\n%s' % ( server, rtable ) )
+            return False
+        if timeout and time >= timeout:
+            error( 'could not connect to %s on port %d\n' % ( server, port ) )
+            return False
+        debug( 'waiting for', server, 'to listen on port', port, '\n' )
+        info( '.' )
         sleep( .5 )
         time += .5
+        result = runCmd( cmd )
     return True
+
+def unitScale( num, prefix='' ):
+    "Return unit scale prefix and factor"
+    scale = 'kMGTP'
+    if prefix:
+        pos = scale.lower().index( prefix.lower() )
+        return prefix, float( 10**(3*(pos+1)) )
+    num, prefix, factor = float( num ), '', 1
+    for i, c in enumerate(scale, start=1):
+        f = 10**(3*i)
+        if num < f:
+            break
+        prefix, factor = c, f
+    return prefix, float( factor )
+
+def fmtBps( bps, prefix='', fmt='%.1f %sbits/sec' ):
+    """Return bps as iperf-style formatted rate string
+       prefix: lock to specific prefix (k, M, G, ...)
+       fmt: default format string for bps, prefix"""
+    bps = float( bps )
+    prefix, factor = unitScale( bps, prefix )
+    bps /= factor
+    return fmt % ( bps, prefix)

mnexec.c

@@ -99,6 +99,7 @@ int main(int argc, char *argv[])
     char path[PATH_MAX];
     int nsid;
     int pid;
+    char *cwd = get_current_dir_name();
 
     static struct sched_param sp;
     while ((c = getopt(argc, argv, "+cdnpa:g:r:vh")) != -1)
@@ -129,6 +130,16 @@ int main(int argc, char *argv[])
                 perror("unshare");
                 return 1;
             }
+
+            /* Mark our whole hierarchy recursively as private, so that our
+             * mounts do not propagate to other processes.
+             */
+
+            if (mount("none", "/", NULL, MS_REC|MS_PRIVATE, NULL) == -1) {
+                perror("remount");
+                return 1;
+            }
+
             /* mount sysfs to pick up the new network namespace */
             if (mount("sysfs", "/sys", "sysfs", MS_MGC_VAL, NULL) == -1) {
                 perror("mount");
@@ -157,18 +168,17 @@ int main(int argc, char *argv[])
             sprintf(path, "/proc/%d/ns/mnt", pid);
             nsid = open(path, O_RDONLY);
             if (nsid < 0 || setns(nsid, 0) != 0) {
-                char *cwd = get_current_dir_name();
                 /* Plan B: chroot/chdir into pid's root file system */
                 sprintf(path, "/proc/%d/root", pid);
                 if (chroot(path) < 0) {
                     perror(path);
                     return 1;
                 }
-                /* need to chdir to correct working directory */
-                if (chdir(cwd) != 0) {
-                    perror(cwd);
-                    return 1;
-                }
+            }
+            /* chdir to correct working directory */
+            if (chdir(cwd) != 0) {
+                perror(cwd);
+                return 1;
             }
             break;
         case 'g':

util/clustersetup.sh

@@ -25,20 +25,20 @@ clean=false
 declare -a hosts=()
 user=$(whoami)
 SSHDIR=/tmp/mn/ssh
-USERDIR=/home/$user/.ssh
-usage=$'./clustersetup.sh [ -p|h|c ] [ host1 ] [ host2 ] ...\n
+USERDIR=$HOME/.ssh
+usage="./clustersetup.sh [ -p|h|c ] [ host1 ] [ host2 ] ...\n
         Authenticate yourself and other cluster nodes to each other
         via ssh for mininet cluster edition. By default, we use a
         temporary ssh setup. An ssh directory is mounted over
-        /home/user/.ssh on each machine in the cluster.
+        $USERDIR on each machine in the cluster.
         
                 -h: display this help
                 -p: create a persistent ssh setup. This will add
                     new ssh keys and known_hosts to each nodes
-                    /home/user/.ssh directory
+                    $USERDIR directory
                 -c: method to clean up a temporary ssh setup.
                     Any hosts taken as arguments will be cleaned
-        '
+        "
 
 persistentSetup() {
     echo "***creating key pair"
@@ -74,40 +74,40 @@ tempSetup() {
     echo "***creating temporary ssh directory"
     mkdir -p $SSHDIR 
     echo "***creating key pair"
-    ssh-keygen -t rsa -C "Cluster_Edition_Key" -f /tmp/mn/ssh/id_rsa -N '' &> /dev/null
+    ssh-keygen -t rsa -C "Cluster_Edition_Key" -f $SSHDIR/id_rsa -N '' &> /dev/null
 
     echo "***mounting temporary ssh directory"
-    sudo mount --bind $SSHDIR /home/$user/.ssh
+    sudo mount --bind $SSHDIR $USERDIR
     cp $SSHDIR/id_rsa.pub $SSHDIR/authorized_keys
 
-for host in $hosts; do
-    echo "***copying public key to $host"
-    ssh-copy-id $user@$host &> /dev/null
-    echo "***mounting remote temporary ssh directory for $host"
-    ssh -o ForwardAgent=yes  $user@$host "
-    mkdir -p /tmp/mn/ssh
-    cp /home/$user/.ssh/authorized_keys $SSHDIR/authorized_keys
-    sudo mount --bind $SSHDIR /home/$user/.ssh"
-    echo "***copying key pair to $host"
-    scp $SSHDIR/{id_rsa,id_rsa.pub} $user@$host:$SSHDIR
-done
+    for host in $hosts; do
+        echo "***copying public key to $host"
+        ssh-copy-id $user@$host &> /dev/null
+        echo "***mounting remote temporary ssh directory for $host"
+        ssh -o ForwardAgent=yes  $user@$host "
+        mkdir -p $SSHDIR
+        cp $USERDIR/authorized_keys $SSHDIR/authorized_keys
+        sudo mount --bind $SSHDIR $USERDIR"
+        echo "***copying key pair to $host"
+        scp $SSHDIR/{id_rsa,id_rsa.pub} $user@$host:$SSHDIR
+    done
 
-for host in $hosts; do
-    echo "***copying known_hosts to $host"
-    scp $SSHDIR/known_hosts $user@$host:$SSHDIR
-done
+    for host in $hosts; do
+        echo "***copying known_hosts to $host"
+        scp $SSHDIR/known_hosts $user@$host:$SSHDIR
+    done
 }
 
 cleanup() {
     
     for host in $hosts; do
     echo "***cleaning up $host"
-    ssh $user@$host "sudo umount /home/$user/.ssh
+    ssh $user@$host "sudo umount $USERDIR
                           sudo rm -rf $SSHDIR"
     done
 
     echo "**unmounting local directories"
-    sudo umount /home/$user/.ssh
+    sudo umount $USERDIR
     echo "***removing temporary ssh directory"
     sudo rm -rf $SSHDIR
     echo "done!"

util/doxify.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/python2
 
 """
 Convert simple documentation to epydoc/pydoctor-compatible markup
@@ -30,7 +30,7 @@ def fixParam( line ):
 def fixReturns( line ):
     "Change returns: foo to @return foo"
     return re.sub( 'returns:', r'@returns', line )
-    
+
 def fixLine( line ):
     global comment
     match = spaces.match( line )
@@ -69,7 +69,7 @@ def funTest():
     ).splitlines( True )
 
     fixLines( testFun )
-    
+
 def fixLines( lines, fid ):
     for line in lines:
         os.write( fid, fixLine( line ) )
@@ -83,7 +83,3 @@ if __name__ == '__main__':
     infile.close()
     os.close( outfid )
     call( [ 'doxypy', outname ] )
-
-
-
-