2.3.1b4 (#1184)

Including changes to mnexec -c to reduce the number of
close() system calls, which may help with performance in
containers on Ubuntu 22.04.

Note that systemd-udevd also seems to be a cause of performance issues
and should probably be disabled while running Mininet.

Adding dbeug logging to test_simpleperf because it is failing
intermittently. (Note with packet loss it can fail, but this
is not how we should be testing it.)

.github/ISSUE_TEMPLATE

@@ -1,4 +1,5 @@
-**Mininet uses GitHub issues for bug reports and feature requests only.**
+<!--
+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**,
@@ -8,7 +9,7 @@ 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.
---- Cut Here ---
+-->
 ### Expected/Desired Behavior:
 
 ### Actual Behavior:

.github/workflows/code-check.yaml

@@ -17,6 +17,6 @@ jobs:
       - name: Install Mininet code check dependencies
         run: |
           PYTHON=`which python` util/install.sh -n
-          python -m pip install pylint==2.4.4
+          python -m pip install pylint==2.15.7
       - name: Run code check
         run:  make codecheck

.github/workflows/run-tests.yaml

@@ -9,43 +9,43 @@ jobs:
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        os: [ubuntu-20.04, ubuntu-18.04, ubuntu-16.04]
-        python-version: [3.x, 2.x]
+        os: [ubuntu-22.04, ubuntu-20.04]
+        py: [python3, python2]
     steps:
       - name: Check out Mininet source
-        uses: actions/checkout@v2
-      - name: Set up Python ${{ matrix.python-version }}
-        uses: actions/setup-python@v2
-        with:
-          python-version: ${{ matrix.python-version }}
+        uses: actions/checkout@v3
+      - name: Install Python ${{ matrix.py }}
+        run: sudo apt install ${{ matrix.py }}
       - name: Install Mininet and base dependencies
         run: |
           sudo apt-get update -qq
           # This seems too slow unfortunately:
           # sudo apt-get upgrade -y -qq
-          PYTHON=`which python` util/install.sh -nv
+          PYTHON=${{ 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"
-          # Verify major python-version number matches python and mininet
-          export PYVER=`echo ${{ matrix.python-version }} | cut -d . -f 1`
-          export CHKVER='px import platform; print(platform.python_version())'
-          python --version |& grep " $PYVER\."
-          echo $CHKVER | $sudo mn -v output | grep " $PYVER\."
+          export PYTHON=${{ matrix.py }}
           # Newer OvS tries OpenFlow15 which crashes ovsc on ubuntu-20.04
           $sudo mn --switch ovs,protocols=OpenFlow13 --test pingall
       - name: Install test dependencies
         run: |
           sudo apt-get install -qq vlan
-          pip install pexpect
+          export PYTHON=${{ 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=`which python`
+          export PYTHON=${{ matrix.py }}
           $sudo $PYTHON mininet/test/runner.py -v
-      - name: Run examples tests (quick)
+      - name: Run examples tests
         run: |
           export sudo="sudo env PATH=$PATH"
-          export PYTHON=`which python`
-          $sudo $PYTHON examples/test/runner.py -v -quick
+          export PYTHON=${{ 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.
@@ -45,12 +45,13 @@ load-plugins=
 # 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=pointless-except, invalid-name, super-init-not-called, fixme, star-args,
+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, bad-whitespace,
-        locally-disabled, locally-enabled, bad-continuation,
+        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
+        no-else-raise, no-else-continue, super-with-arguments,
+        consider-using-f-string, unspecified-encoding
 
 # bad-continuation, wrong-import-order
 
@@ -62,12 +63,12 @@ output-format=colorized
 msg-template='{path}:{line}: [{msg_id}({symbol}), {obj}] {msg}'
 
 # Include message's id in output
-include-ids=yes
+# 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 whether to display a full report or only the messages
 reports=no
@@ -81,7 +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=
@@ -103,7 +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
@@ -144,7 +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
@@ -161,7 +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.
@@ -199,7 +200,7 @@ 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,build
@@ -221,7 +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

INSTALL

@@ -2,7 +2,7 @@
 Mininet Installation/Configuration Notes
 ----------------------------------------
 
-Mininet 2.3.0b2
+Mininet 2.3.1b4
 ---
 
 The supported installation methods for Mininet are 1) using a
@@ -51,7 +51,7 @@ like to contribute an installation script, we would welcome it!)
    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
@@ -124,7 +124,7 @@ like to contribute an installation script, we would welcome it!)
 
    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 versinon of Python:
+   Python, you can run it using that version of Python:
 
        python3 `which mn`
        python2 `which mn`
@@ -137,9 +137,7 @@ like to contribute an installation script, we would welcome it!)
 
    This takes about 4 minutes on our test system.
 
-3.2. Native installation from source on Fedora 18+.
-
-   *This may be out of date.*
+3.2. (Experimental) Native installation from source on Fedora:
 
    As root execute the following operations:
 
@@ -147,21 +145,9 @@ 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
@@ -177,7 +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:
@@ -211,7 +200,10 @@ 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.
+
+Good luck, and have fun!
 
 Mininet Developers
 

LICENSE

@@ -1,33 +1,29 @@
-Mininet 2.3.0b2 License
+BSD 3-Clause License (original Mininet authors: Bob Lantz and Brandon Heller)
 
-Copyright (c) 2013-2020 Open Networking Foundation
-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

@@ -26,14 +26,14 @@ clean:
 codecheck: $(PYSRC)
 	-echo "Running code check"
 	util/versioncheck.py
-	pyflakes $(PYSRC)
+	pyflakes3 $(PYSRC) || pyflakes $(PYSRC)
 	pylint --rcfile=.pylint $(PYSRC)
 #	Exclude miniedit from pep8 checking for now
 	pep8 --repeat --ignore=$(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)
@@ -47,7 +47,8 @@ slowtest: $(MININET)
 	mininet/examples/test/runner.py -v
 
 mnexec: mnexec.c $(MN) mininet/net.py
-	$(CC) $(CFLAGS) $(LDFLAGS) -DVERSION=\"`PYTHONPATH=. $(PYMN) --version`\" $< -o $@
+	$(CC) $(CFLAGS) $(LDFLAGS) \
+	-DVERSION=\"`PYTHONPATH=. $(PYMN) --version 2>&1`\" $< -o $@
 
 install-mnexec: $(MNEXEC)
 	install -D $(MNEXEC) $(BINDIR)/$(MNEXEC)
@@ -56,12 +57,15 @@ 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
 	install $(MNEXEC) $(BINDIR)
 	install $(MANPAGES) $(MANDIR)
+	$(PYTHON) -m pip uninstall -y mininet || true
 	$(PYTHON) -m pip install -e . --no-binary :all:
 
 man: $(MANPAGES)

README.md

@@ -2,7 +2,7 @@ Mininet: Rapid Prototyping for Software Defined Networks
 ========================================================
 *The best way to emulate almost any network on your laptop!*
 
-Mininet 2.3.0b2
+Mininet 2.3.1b4
 
 [![Build Status][1]](https://github.com/mininet/mininet/actions)
 
@@ -70,7 +70,7 @@ Mininet includes:
 
 ### Python 3 Support
 
-- Mininet 2.3.0b2 supports Python 3 and Python 2.
+- Mininet 2.3.1b4 supports Python 3 and Python 2
 
 - You can install both the Python 3 and Python 2 versions of
 Mininet side by side, but the most recent installation will
@@ -82,12 +82,19 @@ determine which Python version is used by default by `mn`.
 
       $ sudo python2 `which mn`
 
+- 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 20.04 LTS (and 18.04 and 16.04)
+- 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.
 
@@ -114,22 +121,22 @@ Mininet mailing list, `mininet-discuss` at:
 
 ### Join Us
 
-Thanks again to all of the Mininet contributors!
+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.
+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.
 
 ### Enjoy Mininet
 
-Best wishes, and we look forward to seeing what you can do with
-Mininet to change the networking world!
+Have fun! We look forward to seeing what you will do with Mininet
+to change the networking world.
 
-Bob Lantz
+Bob Lantz,
 on behalf of the Mininet Contributors
 
 [1]: https://github.com/mininet/mininet/workflows/mininet-tests/badge.svg

bin/mn

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 Mininet runner
@@ -101,7 +101,6 @@ CLI = None  # Set below if needed
 # Locally defined tests
 def allTest( net ):
     "Run ping and iperf tests"
-    net.waitConnected()
     net.start()
     net.ping()
     net.iperf()
@@ -131,7 +130,6 @@ def runTests( mn, options ):
             if callable( testfn ):
                 testfn( mn, *args, **kwargs )
             elif hasattr( mn, test ):
-                mn.waitConnected()
                 getattr( mn, test )( *args, **kwargs )
             else:
                 raise Exception( 'Test %s is unknown - please specify one of '
@@ -191,8 +189,9 @@ class MininetRunner( object ):
             customs = {}
             if os.path.isfile( fileName ):
                 # pylint: disable=exec-used
-                exec( compile( open( fileName ).read(), fileName, 'exec' ),
-                      customs, customs )
+                with open( fileName ) as f:
+                    exec( compile( f.read(), fileName, 'exec' ),
+                          customs, customs )
                 for name, val in customs.items():
                     self.setCustom( name, val )
             else:
@@ -290,6 +289,9 @@ class MininetRunner( object ):
                          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!)' ) )
@@ -386,6 +388,11 @@ class MininetRunner( object ):
                            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=opts.ipbase, inNamespace=opts.innamespace,

examples/README.md

@@ -158,7 +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

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 "This example doesn't use OpenFlow, but attempts to run sshd in a namespace."
 
@@ -27,9 +27,8 @@ h1.setIP( '10.0.0.1', 8 )
 root.setIP( '10.0.0.2', 8 )
 
 info( "*** Creating banner file\n" )
-f = open( '/tmp/%s.banner' % h1.name, 'w' )
-f.write( 'Welcome to %s at %s\n' % ( h1.name, h1.IP() ) )
-f.close()
+with open( '/tmp/%s.banner' % h1.name, 'w' ) as f:
+    f.write( 'Welcome to %s at %s\n' % ( h1.name, h1.IP() ) )
 
 info( "*** Running sshd\n" )
 cmd = '/usr/sbin/sshd -o UseDNS=no -u0 -o "Banner /tmp/%s.banner"' % h1.name

examples/bind.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 bind.py: Bind mount example

examples/cluster.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 cluster.py: prototyping/experimentation for distributed Mininet,
@@ -82,14 +82,13 @@ import sys
 import re
 from itertools import groupby
 from operator import attrgetter
-from distutils.version import StrictVersion
 
 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, errRun
+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
@@ -247,7 +246,7 @@ class RemoteMixin( object ):
         result = ''
         while True:
             poll = popen.poll()
-            result += popen.stdout.read()
+            result += decode( popen.stdout.read() )
             if poll is not None:
                 break
         return result
@@ -314,7 +313,7 @@ class RemoteOVSSwitch( RemoteMixin, OVSSwitch ):
         kwargs.update( batch=True )
         super( RemoteOVSSwitch, self ).__init__( *args, **kwargs )
 
-    def isOldOVS( self ):
+    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:
@@ -376,8 +375,9 @@ class RemoteLink( Link ):
             Link.stop( self )
         self.tunnel = None
 
-    def makeIntfPair( self, intfname1, intfname2, addr1=None, addr2=None,
-                      node1=None, node2=None, deleteIntfs=True   ):
+    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
@@ -440,13 +440,16 @@ 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 != '@':
-            raise Exception( 'makeTunnel:\n',
-                             'Tunnel setup failed for',
-                             '%s:%s' % ( node1, node1.dest ), 'to',
-                             '%s:%s\n' % ( node2, node2.dest ),
-                             'command was:', cmd, '\n' )
+            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 not self.moveIntf( 'tap9', node ):
@@ -778,7 +781,9 @@ class MininetCluster( Mininet ):
         "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
 
@@ -848,27 +853,37 @@ 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 )
-        loopback = '127.0.0.1'
+        controllerIP = controller.IP()
         if ( not isinstance( controller, Controller ) or
-             controller.IP() != loopback ):
-            return None
+             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 is not controller.IP() ]
+                      if ip != controllerIP ]
         if not serverIPs:
             return None  # no remote servers - loopback is fine
-        remoteIP = serverIPs[ 0 ]
-        # 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()
+        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() )
@@ -883,7 +898,10 @@ class MininetCluster( Mininet ):
         Mininet.buildFromTopo( self, *args, **kwargs )
 
 
-def testNsTunnels( remote='ubuntu2', link=RemoteGRELink ):
+# Default remote server for tests
+remoteServer = 'ubuntu2'
+
+def testNsTunnels( remote=remoteServer, link=RemoteGRELink ):
     "Test tunnels between nodes in namespaces"
     net = Mininet( host=RemoteHost, link=link, waitConnected=True )
     h1 = net.addHost( 'h1')
@@ -898,14 +916,14 @@ def testNsTunnels( remote='ubuntu2', link=RemoteGRELink ):
 # This shows how node options may be used to manage
 # cluster placement using the net.add*() API
 
-def testRemoteNet( remote='ubuntu2', link=RemoteGRELink ):
+def testRemoteNet( remote=remoteServer, link=RemoteGRELink ):
     "Test remote Node classes"
     info( '*** Remote Node Test\n' )
-    net = Mininet( host=RemoteHost, switch=RemoteOVSSwitch, link=link,
+    net = Mininet( host=RemoteHost, switch=RemoteOVSSwitch,
+                   link=link, controller=ClusterController,
                    waitConnected=True )
     c0 = net.addController( 'c0' )
     # Make sure controller knows its non-loopback address
-    Intf( 'eth0', node=c0 ).updateIP()
     info( "*** Creating local h1\n" )
     h1 = net.addHost( 'h1' )
     info( "*** Creating remote h2\n" )
@@ -937,7 +955,7 @@ def testRemoteNet( remote='ubuntu2', link=RemoteGRELink ):
 
 remoteHosts = [ 'h2' ]
 remoteSwitches = [ 's2' ]
-remoteServer = 'ubuntu2'
+
 
 def HostPlacer( name, *args, **params ):
     "Custom Host() constructor which places hosts on servers"
@@ -954,10 +972,21 @@ 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( link=RemoteGRELink ):
@@ -974,7 +1003,7 @@ def testRemoteTopo( link=RemoteGRELink ):
 # do random switch placement rather than completely random
 # host placement.
 
-def testRemoteSwitches( remote='ubuntu2', link=RemoteGRELink ):
+def testRemoteSwitches( remote=remoteServer, link=RemoteGRELink ):
     "Test with local hosts and remote switches"
     servers = [ 'localhost', remote]
     topo = TreeTopo( depth=4, fanout=2 )
@@ -992,7 +1021,7 @@ def testRemoteSwitches( remote='ubuntu2', link=RemoteGRELink ):
 # functions, for maximum ease of use. MininetCluster() also
 # pre-flights and multiplexes server connections.
 
-def testMininetCluster( remote='ubuntu2', link=RemoteGRELink ):
+def testMininetCluster( remote=remoteServer, link=RemoteGRELink ):
     "Test MininetCluster()"
     servers = [ 'localhost', remote ]
     topo = TreeTopo( depth=3, fanout=3 )
@@ -1002,7 +1031,7 @@ def testMininetCluster( remote='ubuntu2', link=RemoteGRELink ):
     net.pingAll()
     net.stop()
 
-def signalTest( remote='ubuntu2'):
+def signalTest( remote=remoteServer):
     "Make sure hosts are robust to signals"
     h = RemoteHost( 'h0', server=remote )
     h.shell.send_signal( SIGINT )
@@ -1017,7 +1046,6 @@ def signalTest( remote='ubuntu2'):
 
 if __name__ == '__main__':
     setLogLevel( 'info' )
-    remoteServer = 'ubuntu2'
     remoteLink = RemoteSSHLink
     testRemoteTopo(link=remoteLink)
     testNsTunnels( remote=remoteServer, link=remoteLink )

examples/clustercli.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 "CLI for Mininet Cluster Edition prototype demo"
 

examples/clusterdemo.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 "clusterdemo.py: demo of Mininet Cluster Edition prototype"
 

examples/clusterperf.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 "clusterperf.py compare the maximum throughput between SSH and GRE tunnels"
 

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
@@ -69,7 +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."
@@ -111,10 +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."
@@ -294,10 +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' )

examples/controllers.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 Create a network where different switches are connected to

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

examples/controlnet.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 controlnet.py: Mininet with a custom control network

examples/cpu.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 cpu.py: test iperf bandwidth for varying cpu limits
@@ -68,11 +68,16 @@ def bwtest( cpuLimits, period_us=100000, seconds=10 ):
             # the client's buffer fill rate
             popen = server.popen( 'iperf -yc -s -p 5001' )
             waitListening( client, server, 5001 )
-            # ignore empty result from waitListening/telnet
-            popen.stdout.readline()
             client.cmd( 'iperf -yc -t %s -c %s' % ( seconds, server.IP() ) )
-            result = decode( popen.stdout.readline() ).split( ',' )
-            bps = float( result[ -1 ] )
+            # 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, [] )

examples/emptynet.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 This example shows how to create an empty Mininet object

examples/hwintf.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 This example shows how to add an interface (for example a real

examples/intfoptions.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 '''
 example of using various TCIntf options.

examples/limit.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 limit.py: example of using link and CPU limits

examples/linearbandwidth.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 Test bandwidth (using iperf) on linear networks of varying size,
@@ -83,9 +83,8 @@ def linearBandwidthTest( lengths ):
     output = quietRun( 'sysctl -w net.ipv4.tcp_congestion_control=reno' )
     assert 'reno' in output
 
-    for datapath in switches:
+    for datapath, Switch in switches.items():
         info( "*** testing", datapath, "datapath\n" )
-        Switch = switches[ datapath ]
         results[ datapath ] = []
         link = partial( TCLink, delay='30ms', bw=100 )
         net = Mininet( topo=topo, switch=Switch,

examples/linuxrouter.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 linuxrouter.py: Example network with Linux IP router

examples/miniedit.py

@@ -18,16 +18,15 @@ import os
 import re
 import sys
 
-from distutils.version import StrictVersion
 from functools import partial
-from optparse import OptionParser
+from optparse import OptionParser  # pylint: disable=deprecated-module
 from subprocess import call
 from sys import exit  # pylint: disable=redefined-builtin
 
 from mininet.log import info, debug, warn, setLogLevel
 from mininet.net import Mininet, VERSION
 from mininet.util import (netParse, ipAdd, quietRun,
-                          buildTopo, custom, customClass )
+                          buildTopo, custom, customClass, StrictVersion )
 from mininet.term import makeTerm, cleanUpScreens
 from mininet.node import (Controller, RemoteController, NOX, OVSController,
                           CPULimitedHost, Host, Node,
@@ -1363,7 +1362,7 @@ class MiniEdit( Frame ):
 
         # Tools
         for tool in self.tools:
-            cmd = ( lambda t=tool: self.activate( t ) )
+            cmd = partial( self.activate, tool )
             b = Button( toolbar, text=tool, font=self.smallFont, command=cmd)
             if tool in self.images:
                 b.config( height=35, image=self.images[ tool ] )
@@ -1421,10 +1420,7 @@ class MiniEdit( Frame ):
 
     def convertJsonUnicode(self, text):
         "Some part of Mininet don't like Unicode"
-        try:
-            unicode
-        except NameError:
-            return text
+        unicode = globals.get( 'unicode', str )
         if isinstance(text, dict):
             return {self.convertJsonUnicode(key): self.convertJsonUnicode(value) for key, value in text.items()}
         if isinstance(text, list):
@@ -1449,7 +1445,7 @@ class MiniEdit( Frame ):
 
         # Load application preferences
         if 'application' in loadedTopology:
-            self.appPrefs = dict(self.appPrefs.items() + loadedTopology['application'].items())
+            self.appPrefs.update(loadedTopology['application'])
             if "ovsOf10" not in self.appPrefs["openFlowVersions"]:
                 self.appPrefs["openFlowVersions"]["ovsOf10"] = '0'
             if "ovsOf11" not in self.appPrefs["openFlowVersions"]:
@@ -1607,7 +1603,7 @@ class MiniEdit( Frame ):
 
     def newTopology( self ):
         "New command."
-        for widget in self.widgetToItem:
+        for widget in tuple( self.widgetToItem ):
             self.deleteItem( self.widgetToItem[ widget ] )
         self.hostCount = 0
         self.switchCount = 0
@@ -1635,10 +1631,10 @@ class MiniEdit( Frame ):
             hostsToSave = []
             switchesToSave = []
             controllersToSave = []
-            for widget in self.widgetToItem:
+            for widget, item in self.widgetToItem.items():
                 name = widget[ 'text' ]
-                tags = self.canvas.gettags( self.widgetToItem[ widget ] )
-                x1, y1 = self.canvas.coords( self.widgetToItem[ widget ] )
+                tags = self.canvas.gettags( item )
+                x1, y1 = self.canvas.coords( item )
                 if 'Switch' in tags or 'LegacySwitch' in tags or 'LegacyRouter' in tags:
                     nodeNum = self.switchOpts[name]['nodeNum']
                     nodeToSave = {'number':str(nodeNum),
@@ -1683,14 +1679,13 @@ class MiniEdit( Frame ):
             savingDictionary['application'] = self.appPrefs
 
             try:
-                f = open(fileName, 'wb')
-                f.write(json.dumps(savingDictionary, sort_keys=True, indent=4, separators=(',', ': ')))
-            # pylint: disable=broad-except
-            except Exception as er:
+                with open(fileName, 'w') as f:
+                    f.write(
+                        json.dumps(savingDictionary,
+                                   sort_keys=True,
+                                   indent=4, separators=(',', ': ')))
+            except Exception as er:  # pylint: disable=broad-except
                 warn( er, '\n' )
-            # pylint: enable=broad-except
-            finally:
-                f.close()
 
     def exportScript( self ):
         "Export command."
@@ -1702,9 +1697,9 @@ class MiniEdit( Frame ):
         fileName = tkFileDialog.asksaveasfilename(filetypes=myFormats ,title="Export the topology as...")
         if len(fileName ) > 0:
             # debug( "Now saving under %s\n" % fileName )
-            f = open(fileName, 'wb')
+            f = open(fileName, 'w')  # pylint: disable=consider-using-with
 
-            f.write("#!/usr/bin/python\n")
+            f.write("#!/usr/bin/env python\n")
             f.write("\n")
             f.write("from mininet.net import Mininet\n")
             f.write("from mininet.node import Controller, RemoteController, OVSController\n")
@@ -1718,9 +1713,9 @@ class MiniEdit( Frame ):
             f.write("from subprocess import call\n")
 
             inBandCtrl = False
-            for widget in self.widgetToItem:
+            for widget, item in self.widgetToItem.items():
                 name = widget[ 'text' ]
-                tags = self.canvas.gettags( self.widgetToItem[ widget ] )
+                tags = self.canvas.gettags( item )
 
                 if 'Controller' in tags:
                     opts = self.controllers[name]
@@ -1746,9 +1741,9 @@ class MiniEdit( Frame ):
             f.write("                   ipBase='"+self.appPrefs['ipBase']+"')\n")
             f.write("\n")
             f.write("    info( '*** Adding controller\\n' )\n")
-            for widget in self.widgetToItem:
+            for widget, item in self.widgetToItem.items():
                 name = widget[ 'text' ]
-                tags = self.canvas.gettags( self.widgetToItem[ widget ] )
+                tags = self.canvas.gettags( item )
 
                 if 'Controller' in tags:
                     opts = self.controllers[name]
@@ -1780,9 +1775,9 @@ class MiniEdit( Frame ):
 
             # Save Switches and Hosts
             f.write("    info( '*** Add switches\\n')\n")
-            for widget in self.widgetToItem:
+            for widget, item in self.widgetToItem.items():
                 name = widget[ 'text' ]
-                tags = self.canvas.gettags( self.widgetToItem[ widget ] )
+                tags = self.canvas.gettags( item )
                 if 'LegacyRouter' in tags:
                     f.write("    "+name+" = net.addHost('"+name+"', cls=Node, ip='0.0.0.0')\n")
                     f.write("    "+name+".cmd('sysctl -w net.ipv4.ip_forward=1')\n")
@@ -1820,9 +1815,9 @@ class MiniEdit( Frame ):
 
             f.write("\n")
             f.write("    info( '*** Add hosts\\n')\n")
-            for widget in self.widgetToItem:
+            for widget, item in self.widgetToItem.items():
                 name = widget[ 'text' ]
-                tags = self.canvas.gettags( self.widgetToItem[ widget ] )
+                tags = self.canvas.gettags( item )
                 if 'Host' in tags:
                     opts = self.hostOpts[name]
                     ip = None
@@ -1915,9 +1910,9 @@ class MiniEdit( Frame ):
             f.write("\n")
 
             f.write("    info( '*** Starting switches\\n')\n")
-            for widget in self.widgetToItem:
+            for widget, item in self.widgetToItem.items():
                 name = widget[ 'text' ]
-                tags = self.canvas.gettags( self.widgetToItem[ widget ] )
+                tags = self.canvas.gettags( item )
                 if 'Switch' in tags or 'LegacySwitch' in tags:
                     opts = self.switchOpts[name]
                     ctrlList = ",".join(opts['controllers'])
@@ -1926,9 +1921,9 @@ class MiniEdit( Frame ):
             f.write("\n")
 
             f.write("    info( '*** Post configure switches and hosts\\n')\n")
-            for widget in self.widgetToItem:
+            for widget, item in self.widgetToItem.items():
                 name = widget[ 'text' ]
-                tags = self.canvas.gettags( self.widgetToItem[ widget ] )
+                tags = self.canvas.gettags( item )
                 if 'Switch' in tags:
                     opts = self.switchOpts[name]
                     if opts['switchType'] == 'default':
@@ -1956,9 +1951,9 @@ class MiniEdit( Frame ):
                         if 'switchIP' in opts:
                             if len(opts['switchIP']) > 0:
                                 f.write("    "+name+".cmd('ifconfig "+name+" "+opts['switchIP']+"')\n")
-            for widget in self.widgetToItem:
+            for widget, item in self.widgetToItem.items():
                 name = widget[ 'text' ]
-                tags = self.canvas.gettags( self.widgetToItem[ widget ] )
+                tags = self.canvas.gettags( item )
                 if 'Host' in tags:
                     opts = self.hostOpts[name]
                     # Attach vlan interfaces
@@ -1980,9 +1975,9 @@ class MiniEdit( Frame ):
             if len(nflowValues['nflowTarget']) > 0:
                 nflowEnabled = False
                 nflowSwitches = ''
-                for widget in self.widgetToItem:
+                for widget, item in self.widgetToItem.items():
                     name = widget[ 'text' ]
-                    tags = self.canvas.gettags( self.widgetToItem[ widget ] )
+                    tags = self.canvas.gettags( item )
 
                     if 'Switch' in tags:
                         opts = self.switchOpts[name]
@@ -2004,9 +1999,9 @@ class MiniEdit( Frame ):
             if len(sflowValues['sflowTarget']) > 0:
                 sflowEnabled = False
                 sflowSwitches = ''
-                for widget in self.widgetToItem:
+                for widget, item in self.widgetToItem.items():
                     name = widget[ 'text' ]
-                    tags = self.canvas.gettags( self.widgetToItem[ widget ] )
+                    tags = self.canvas.gettags( item )
 
                     if 'Switch' in tags:
                         opts = self.switchOpts[name]
@@ -2021,9 +2016,9 @@ class MiniEdit( Frame ):
 
             f.write("\n")
             f.write("    CLI(net)\n")
-            for widget in self.widgetToItem:
+            for widget, item in self.widgetToItem:
                 name = widget[ 'text' ]
-                tags = self.canvas.gettags( self.widgetToItem[ widget ] )
+                tags = self.canvas.gettags( item )
                 if 'Host' in tags:
                     opts = self.hostOpts[name]
                     # Run User Defined Stop Command
@@ -2445,7 +2440,8 @@ class MiniEdit( Frame ):
             line3.pack(pady=10 )
             line4.pack(pady=10 )
             line5.pack(pady=10 )
-            hide = ( lambda about=about: about.withdraw() )
+            def hide():
+                about.withdraw()
             self.aboutBox = about
             # Hide on close rather than destroying window
             Wm.wm_protocol( about, name='WM_DELETE_WINDOW', func=hide )
@@ -2620,9 +2616,9 @@ class MiniEdit( Frame ):
             info( 'New controller details for ' + name + ' = ' + str(self.controllers[name]), '\n' )
             # Find references to controller and change name
             if oldName != name:
-                for widget in self.widgetToItem:
+                for widget, item in self.widgetToItem.items():
                     switchName = widget[ 'text' ]
-                    tags = self.canvas.gettags( self.widgetToItem[ widget ] )
+                    tags = self.canvas.gettags( item )
                     if 'Switch' in tags:
                         switch = self.switchOpts[switchName]
                         if oldName in switch['controllers']:
@@ -2703,14 +2699,13 @@ class MiniEdit( Frame ):
         tags = self.canvas.gettags(item)
         if 'Controller' in tags:
             # remove from switch controller lists
-            for serachwidget in self.widgetToItem:
-                name = serachwidget[ 'text' ]
-                tags = self.canvas.gettags( self.widgetToItem[ serachwidget ] )
+            for searchwidget, searchitem in self.widgetToItem.items():
+                name = searchwidget[ 'text' ]
+                tags = self.canvas.gettags( searchitem )
                 if 'Switch' in tags:
                     if widget['text'] in self.switchOpts[name]['controllers']:
                         self.switchOpts[name]['controllers'].remove(widget['text'])
-
-        for link in widget.links.values():
+        for link in tuple( widget.links.values() ):
             # Delete from view and model
             self.deleteItem( link )
         del self.itemToWidget[ item ]
@@ -2719,9 +2714,9 @@ class MiniEdit( Frame ):
     def buildNodes( self, net):
         # Make nodes
         info( "Getting Hosts and Switches.\n" )
-        for widget in self.widgetToItem:
+        for widget, item in self.widgetToItem.items():
             name = widget[ 'text' ]
-            tags = self.canvas.gettags( self.widgetToItem[ widget ] )
+            tags = self.canvas.gettags( item )
             # debug( name+' has '+str(tags), '\n' )
 
             if 'Switch' in tags:
@@ -2935,9 +2930,9 @@ class MiniEdit( Frame ):
     def postStartSetup( self ):
 
         # Setup host details
-        for widget in self.widgetToItem:
+        for widget, item in self.widgetToItem.items():
             name = widget[ 'text' ]
-            tags = self.canvas.gettags( self.widgetToItem[ widget ] )
+            tags = self.canvas.gettags( item )
             if 'Host' in tags:
                 newHost = self.net.get(name)
                 opts = self.hostOpts[name]
@@ -2962,9 +2957,9 @@ class MiniEdit( Frame ):
         if len(nflowValues['nflowTarget']) > 0:
             nflowEnabled = False
             nflowSwitches = ''
-            for widget in self.widgetToItem:
+            for widget, item in self.widgetToItem.items():
                 name = widget[ 'text' ]
-                tags = self.canvas.gettags( self.widgetToItem[ widget ] )
+                tags = self.canvas.gettags( item )
 
                 if 'Switch' in tags:
                     opts = self.switchOpts[name]
@@ -2992,9 +2987,9 @@ class MiniEdit( Frame ):
         if len(sflowValues['sflowTarget']) > 0:
             sflowEnabled = False
             sflowSwitches = ''
-            for widget in self.widgetToItem:
+            for widget, item in self.widgetToItem.items():
                 name = widget[ 'text' ]
-                tags = self.canvas.gettags( self.widgetToItem[ widget ] )
+                tags = self.canvas.gettags( item )
 
                 if 'Switch' in tags:
                     opts = self.switchOpts[name]
@@ -3037,9 +3032,9 @@ class MiniEdit( Frame ):
             #for switch in self.net.switches:
             #    info( switch.name + ' ')
             #    switch.start( self.net.controllers )
-            for widget in self.widgetToItem:
+            for widget, item in self.widgetToItem.items():
                 name = widget[ 'text' ]
-                tags = self.canvas.gettags( self.widgetToItem[ widget ] )
+                tags = self.canvas.gettags( item )
                 if 'Switch' in tags:
                     opts = self.switchOpts[name]
                     switchControllers = []
@@ -3059,9 +3054,9 @@ class MiniEdit( Frame ):
         "Stop network."
         if self.net is not None:
             # Stop host details
-            for widget in self.widgetToItem:
+            for widget, item in self.widgetToItem.items():
                 name = widget[ 'text' ]
-                tags = self.canvas.gettags( self.widgetToItem[ widget ] )
+                tags = self.canvas.gettags( item )
                 if 'Host' in tags:
                     newHost = self.net.get(name)
                     opts = self.hostOpts[name]
@@ -3204,7 +3199,7 @@ class MiniEdit( Frame ):
         addDictOption( opts, LINKS, LINKDEF, 'link' )
 
         opts.add_option( '--custom', type='string', default=None,
-                         help='read custom topo and node params from .py' +
+                         help='read custom topo and node params from .py ' +
                          'file' )
 
         self.options, self.args = opts.parse_args()

examples/mobility.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 Simple example of Mobility with Mininet

examples/multilink.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 This is a simple example that demonstrates multiple links

examples/multiping.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 multiping.py: monitor multiple sets of hosts using ping
@@ -17,9 +17,9 @@ from mininet.topo import SingleSwitchTopo
 from mininet.log import info, setLogLevel
 
 
-def chunks( l, n ):
+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"

examples/multipoll.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 Simple example of sending output to multiple files and
@@ -18,11 +18,12 @@ 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.items():
-        tail = Popen( [ 'tail', '-f', outfile ],
-                      stdout=PIPE, stderr=devnull )
+        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

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.

examples/nat.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 Example to create a Mininet topology and connect it to the internet via NAT

examples/natnet.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 natnet.py: Example network with NATs

examples/numberedports.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 Create a network with 5 hosts, numbered 1-4 and 9.

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

examples/popenpoll.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 "Monitor multiple hosts using popen()/pmonitor()"
 

examples/scratchnet.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 Build a simple network from scratch, using mininet primitives.

examples/scratchnetuser.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 Build a simple network from scratch, using mininet primitives.

examples/simpleperf.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 """
 Simple example of setting network and CPU parameters
@@ -49,13 +49,19 @@ def perfTest( lossy=True ):
     net.start()
     info( "Dumping host connections\n" )
     dumpNodeConnections(net.hosts)
-    info( "Testing bandwidth between h1 and h4\n" )
+    info( "Testing bandwidth between h1 and h4 (lossy=%s)\n" % lossy )
     h1, h4 = net.getNodeByName('h1', 'h4')
     net.iperf( ( h1, h4 ), l4Type='UDP' )
+    # Debugging
+    h1.cmd('jobs')
+    h4.cmd('jobs')
     net.stop()
 
 
 if __name__ == '__main__':
     setLogLevel( 'info' )
+    # Debug for now
+    if 'testmode' in argv:
+        setLogLevel( 'debug' )
     # 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.

examples/test/test_simpleperf.py

@@ -19,9 +19,12 @@ class testSimplePerf( unittest.TestCase ):
         # 10 Mb/s, plus or minus 20% tolerance
         BW = 10
         TOLERANCE = .2
-        p = pexpect.spawn( 'python -m mininet.examples.simpleperf testmode' )
+        p = pexpect.spawn(
+            'python -m mininet.examples.simpleperf testmode' )
+        # Log since this seems to be failing intermittently
+        p.logfile = sys.stdout
         # check iperf results
-        p.expect( "Results: \['10M', '([\d\.]+) .bits/sec", timeout=480 )
+        p.expect( "Results: \['10M', '([\d\.]+) .bits/sec", timeout=90 )
         measuredBw = float( p.match.group( 1 ) )
         lowerBound = BW * ( 1 - TOLERANCE )
         upperBound = BW + ( 1 + TOLERANCE )
@@ -30,5 +33,5 @@ class testSimplePerf( unittest.TestCase ):
         p.wait()
 
 if __name__ == '__main__':
-    setLogLevel( 'warning' )
+    setLogLevel( 'debug' )
     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.

examples/treeping64.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 "Create a 64-node tree network, and test connectivity using ping."
 
@@ -25,9 +25,8 @@ def treePing64():
     switches = { 'reference user': UserSwitch,
                  'Open vSwitch kernel': OVSKernelSwitch }
 
-    for name in switches:
+    for name, switch in switches.items():
         info( "*** Testing", name, "datapath\n" )
-        switch = switches[ name ]
         network = TreeNet( depth=2, fanout=8, switch=switch,
                            waitConnected=True )
         result = network.run( network.pingAll )

mininet/__main__.py

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

mininet/clean.py

@@ -21,7 +21,9 @@ from mininet.util import decode
 def sh( cmd ):
     "Print a command and send it to the shell"
     info( cmd + '\n' )
-    result = 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 ):
@@ -51,9 +53,9 @@ class Cleanup( object ):
 
         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' )
+        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.

mininet/cli.py

@@ -89,7 +89,15 @@ class CLI( Cmd ):
             if os.path.isfile( history_path ):
                 read_history_file( history_path )
                 set_history_length( 1000 )
-            atexit.register( lambda: write_history_file( history_path ) )
+
+            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"
@@ -142,7 +150,7 @@ class CLI( Cmd ):
         '  mininet> xterm h2\n\n'
     )
 
-    def do_help( self, line ):  # pylint: disable=arguments-differ
+    def do_help( self, line ):  # pylint: disable=arguments-renamed
         "Describe available CLI commands."
         Cmd.do_help( self, line )
         if line == '':
@@ -176,7 +184,7 @@ class CLI( Cmd ):
         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' )
@@ -344,13 +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()
@@ -448,12 +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 != '':
                         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 )

mininet/link.py

@@ -316,8 +316,9 @@ class TCIntf( Intf ):
         debug(" *** executing command: %s\n" % c)
         return self.cmd( c )
 
-    # pylint: disable=arguments-differ
-    def config( self, bw=None, delay=None, jitter=None, loss=None,
+    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,
@@ -539,9 +540,7 @@ class OVSLink( Link ):
 
     def __init__( self, node1, node2, **kwargs ):
         "See Link.__init__() for options"
-        try:
-            OVSSwitch
-        except NameError:
+        if 'OVSSwitch' not in globals():
             # pylint: disable=import-outside-toplevel,cyclic-import
             from mininet.node import OVSSwitch
         self.isPatchLink = False
@@ -551,7 +550,7 @@ class OVSLink( Link ):
             kwargs.update( cls1=OVSIntf, cls2=OVSIntf )
         Link.__init__( self, node1, node2, **kwargs )
 
-    # pylint: disable=arguments-differ, signature-differs
+    # pylint: disable=arguments-renamed, arguments-differ, signature-differs
     def makeIntfPair( self, *args, **kwargs ):
         "Usually delegated to OVSSwitch"
         if self.isPatchLink:

mininet/net.py

@@ -98,18 +98,18 @@ 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.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,
                            macColonHex, ipStr, ipParse, netParse, ipAdd,
-                           waitListening, BaseString )
+                           waitListening, BaseString, fmtBps )
 from mininet.term import cleanUpScreens, makeTerms
 
 # Mininet version: should be consistent with README and LICENSE
-VERSION = "2.3.0b2"
+VERSION = "2.3.1b4"
 
 class Mininet( object ):
     "Network emulation with hosts spawned in network namespaces."
@@ -137,7 +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
@@ -175,15 +177,17 @@ class Mininet( object ):
         if topo and build:
             self.build()
 
-    def waitConnected( self, timeout=5, delay=.5 ):
-        """wait for each switch to connect to a controller,
-           up to 5 seconds
-           timeout: time to wait, or None to wait indefinitely
+    def waitConnected( self, timeout=None, delay=.5 ):
+        """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():
@@ -192,12 +196,12 @@ class Mininet( object ):
             if not remaining:
                 info( '\n' )
                 return True
-            if timeout is not None and time > timeout:
+            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 )
@@ -559,7 +563,7 @@ class Mininet( object ):
                 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"
@@ -568,6 +572,10 @@ 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()
@@ -667,7 +675,7 @@ class Mininet( object ):
                     if timeout:
                         opts = '-W %s' % timeout
                     if dest.intfs:
-                        result = node.cmd( 'ping -c1 %s %s' %
+                        result = node.cmd( 'LANG=C ping -c1 %s %s' %
                                            (opts, dest.IP()) )
                         sent, received = self._parsePing( result )
                     else:
@@ -778,18 +786,26 @@ 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
 
@@ -799,7 +815,7 @@ class Mininet( object ):
            hosts: list of hosts; if None, uses first and last hosts
            l4Type: string, one of [ TCP, UDP ]
            udpBw: bandwidth target for UDP test
-           fmt: iperf format argument if any
+           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
@@ -812,33 +828,34 @@ class Mininet( object ):
         output( '*** Iperf: testing', l4Type, 'bandwidth between',
                 client, 'and', server, '\n' )
         server.cmd( 'killall -9 iperf' )
-        iperfArgs = 'iperf -p %d ' % port
+        # 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 fmt:
-            iperfArgs += '-f %s ' % fmt
         server.sendCmd( iperfArgs + '-s' )
+        serverip = server.IP()
         if l4Type == 'TCP':
-            if not waitListening( client, server.IP(), port ):
+            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 )
-        debug( 'Client output: %s\n' % cliout )
-        servout = ''
-        # We want the last *b/sec from the iperf server output
-        # for TCP, there are two of them because of waitListening
-        count = 2 if l4Type == 'TCP' else 1
-        while len( re.findall( '/sec', servout ) ) < count:
-            servout += server.monitor( timeoutms=5000 )
+        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 )

mininet/node.py

@@ -57,7 +57,6 @@ import pty
 import re
 import signal
 import select
-from distutils.version import StrictVersion
 from re import findall
 from subprocess import Popen, PIPE
 from sys import exit  # pylint: disable=redefined-builtin
@@ -66,7 +65,8 @@ from time import sleep
 from mininet.log import info, error, warn, debug
 from mininet.util import ( quietRun, errRun, errFail, moveIntf, isShellBuiltin,
                            numCores, retry, mountCgroups, BaseString, decode,
-                           encode, getincrementaldecoder, Python3, which )
+                           encode, getincrementaldecoder, Python3, which,
+                           StrictVersion )
 from mininet.moduledeps import moduleDeps, pathCheck, TUN
 from mininet.link import Link, Intf, TCIntf, OVSIntf
 
@@ -219,7 +219,7 @@ class Node( object ):
             params: parameters to Popen()"""
         # Leave this is as an instance method for now
         assert self
-        popen = Popen( cmd, **params )
+        popen = Popen( cmd, **params )  # pylint: disable=consider-using-with
         debug( '_popen', cmd, popen.pid )
         return popen
 
@@ -685,8 +685,21 @@ class CPULimitedHost( Host ):
 
     "CPU limited host"
 
-    def __init__( self, name, sched='cfs', **kwargs ):
-        Host.__init__( self, name, **kwargs )
+    def __init__( self, name, sched='cfs', **params ):
+        Host.__init__( self, name, **params )
+        # BL: Setting the correct period/quota is tricky, particularly
+        # for RT. RT allows very small quotas, but the overhead
+        # seems to be high. CFS has a mininimum quota of 1 ms, but
+        # still does better with larger period values.
+        self.period_us = params.get( 'period_us', 100000 )
+        self.sched = sched
+        self.cgroupsInited = False
+        self.cgroup, self.rtprio = None, None
+
+    def initCgroups( self ):
+        "Deferred cgroup initialization"
+        if self.cgroupsInited:
+            return
         # Initialize class if necessary
         if not CPULimitedHost.inited:
             CPULimitedHost.init()
@@ -696,32 +709,26 @@ class CPULimitedHost( Host ):
         # We don't add ourselves to a cpuset because you must
         # specify the cpu and memory placement first
         errFail( 'cgclassify -g cpu,cpuacct:/%s %s' % ( self.name, self.pid ) )
-        # BL: Setting the correct period/quota is tricky, particularly
-        # for RT. RT allows very small quotas, but the overhead
-        # seems to be high. CFS has a mininimum quota of 1 ms, but
-        # still does better with larger period values.
-        self.period_us = kwargs.get( 'period_us', 100000 )
-        self.sched = sched
-        if sched == 'rt':
+        if self.sched == 'rt':
             self.checkRtGroupSched()
             self.rtprio = 20
 
     def cgroupSet( self, param, value, resource='cpu' ):
         "Set a cgroup parameter and return its value"
-        cmd = 'cgset -r %s.%s=%s /%s' % (
-            resource, param, value, self.name )
-        quietRun( cmd )
-        nvalue = int( self.cgroupGet( param, resource ) )
-        if nvalue != value:
+        cmd = [ 'cgset', '-r', "%s.%s=%s" % (
+            resource, param, value), '/' + self.name ]
+        errFail( cmd )
+        nvalue = self.cgroupGet( param, resource )
+        if nvalue != str( value ):
             error( '*** error: cgroupSet: %s set to %s instead of %s\n'
                    % ( param, nvalue, value ) )
         return nvalue
 
     def cgroupGet( self, param, resource='cpu' ):
         "Return value of cgroup parameter"
-        cmd = 'cgget -r %s.%s /%s' % (
-            resource, param, self.name )
-        return int( quietRun( cmd ).split()[ -1 ] )
+        pname = '%s.%s' % ( resource, param )
+        cmd = 'cgget -n -r %s /%s' % ( pname, self.name )
+        return quietRun( cmd )[len(pname)+1:].strip()
 
     def cgroupDel( self ):
         "Clean up our cgroup"
@@ -788,6 +795,8 @@ class CPULimitedHost( Host ):
     def cfsInfo( self, f ):
         "Internal method: return parameters for CFS bandwidth"
         pstr, qstr = 'cfs_period_us', 'cfs_quota_us'
+        if self.cgversion == 'cgroup2':
+            pstr, qstr = 'max', ''
         # CFS uses wall clock time for period and CPU time for quota.
         quota = int( self.period_us * f * numCores() )
         period = self.period_us
@@ -797,7 +806,7 @@ class CPULimitedHost( Host ):
             period = int( quota / f / numCores() )
         # Reset to unlimited on negative quota
         if quota < 0:
-            quota = -1
+            quota = 'max' if self.cgversion == 'cgroup2' else -1
         return pstr, qstr, period, quota
 
     # BL comment:
@@ -827,12 +836,16 @@ class CPULimitedHost( Host ):
         else:
             return
         # Set cgroup's period and quota
-        setPeriod = self.cgroupSet( pstr, period )
-        setQuota = self.cgroupSet( qstr, quota )
+        if self.cgversion == 'cgroup':
+            setPeriod = self.cgroupSet( pstr, period )
+            setQuota = self.cgroupSet( qstr, quota )
+        else:
+            setQuota, setPeriod = self.cgroupSet(
+                    pstr, '%s %s' % (quota, period) ).split()
         if sched == 'rt':
             # Set RT priority if necessary
             sched = self.chrt()
-        info( '(%s %d/%dus) ' % ( sched, setQuota, setPeriod ) )
+        info( '(%s %s/%dus) ' % ( sched, setQuota, int( setPeriod ) ) )
 
     def setCPUs( self, cores, mems=0 ):
         "Specify (real) cores that our cgroup can run on"
@@ -857,6 +870,7 @@ class CPULimitedHost( Host ):
            cores: (real) core(s) this host can run on
            params: parameters for Node.config()"""
         r = Node.config( self, **params )
+        self.initCgroups()
         # Was considering cpu={'cpu': cpu , 'sched': sched}, but
         # that seems redundant
         self.setParam( r, 'setCPUFrac', cpu=cpu )
@@ -864,13 +878,19 @@ class CPULimitedHost( Host ):
         return r
 
     inited = False
+    cgversion = 'cgroup2'
 
     @classmethod
     def init( cls ):
         "Initialization for CPULimitedHost class"
-        mountCgroups()
+        cls.cgversion = mountCgroups()
         cls.inited = True
 
+    def unlimit( self ):
+        "Unlimit cpu for cfs"
+        if self.sched == 'cfs' and self.params.get( 'cpu', -1 ) != -1:
+            self.setCPUFrac( -1, sched=self.sched )
+
 
 # Some important things to note:
 #
@@ -1505,32 +1525,26 @@ class NOX( Controller ):
 
         Controller.__init__( self, name,
                              command=noxCoreDir + '/nox_core',
-                             cargs='--libdir=/usr/local/lib -v -i ptcp:%s ' +
+                             cargs='--libdir=/usr/local/lib -v '
+                             '-i ptcp:%s ' +
                              ' '.join( noxArgs ),
                              cdir=noxCoreDir,
                              **kwargs )
 
 class Ryu( Controller ):
-    "Controller to run Ryu application"
-    def __init__( self, name, *ryuArgs, **kwargs ):
+    "Ryu OpenFlow Controller"
+    def __init__( self, name, ryuArgs='ryu.app.simple_switch',
+                  command='ryu run', **kwargs ):
         """Init.
-        name: name to give controller.
-        ryuArgs: arguments and modules to pass to Ryu"""
-        homeDir = quietRun( 'printenv HOME' ).strip( '\r\n' )
-        ryuCoreDir = '%s/ryu/ryu/app/' % homeDir
-        if not ryuArgs:
-            warn( 'warning: no Ryu modules specified; '
-                  'running simple_switch only\n' )
-            ryuArgs = [ ryuCoreDir + 'simple_switch.py' ]
-        elif not isinstance( ryuArgs, ( list, tuple ) ):
-            ryuArgs = [ ryuArgs ]
-
-        Controller.__init__( self, name,
-                             command='ryu-manager',
-                             cargs='--ofp-tcp-listen-port %s ' +
-                             ' '.join( ryuArgs ),
-                             cdir=ryuCoreDir,
-                             **kwargs )
+           name: name to give controller.
+           ryuArgs: modules to pass to Ryu (ryu.app.simple_switch)
+           command: command to run Ryu ('ryu run')"""
+        if isinstance( ryuArgs, ( list, tuple ) ):
+            ryuArgs = ' '.join( ryuArgs )
+        cargs = kwargs.pop(
+            'cargs', ryuArgs + ' --ofp-tcp-listen-port %s' )
+        Controller.__init__( self, name, command=command,
+                             cargs=cargs, **kwargs )
 
 
 class RemoteController( Controller ):

mininet/test/test_walkthrough.py

@@ -10,10 +10,9 @@ import os
 import re
 import unittest
 
-from distutils.version import StrictVersion
 from sys import stdout
 
-from mininet.util import quietRun, pexpect
+from mininet.util import quietRun, pexpect, StrictVersion
 from mininet.clean import cleanup
 
 
@@ -132,7 +131,7 @@ class testWalkthrough( unittest.TestCase ):
                 ifcount += 1
             else:
                 break
-        self.assertTrue( 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 )

mininet/topo.py

@@ -336,9 +336,11 @@ class LinearTopo( Topo ):
         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 ):

mininet/topolib.py

@@ -53,9 +53,11 @@ class TorusTopo( Topo ):
             raise Exception( 'Please use 3x3 or greater for compatibility '
                              'with 2.1' )
         if n == 1:
-            genHostName = lambda loc, k: 'h%s' % ( loc )
+            def genHostName( loc, _k ):
+                return 'h%s' % ( loc )
         else:
-            genHostName = lambda loc, k: 'h%sx%d' % ( loc, k )
+            def genHostName( loc, k ):
+                return 'h%sx%d' % ( loc, k )
 
         hosts, switches, dpid = {}, {}, 0
         # Create and wire interior

mininet/util.py

@@ -5,6 +5,7 @@ import os
 import re
 import sys
 
+from collections import namedtuple
 from fcntl import fcntl, F_GETFL, F_SETFL
 from functools import partial
 from os import O_NONBLOCK
@@ -46,6 +47,7 @@ if Python3:
         "Encode buffer for Python 3"
         return buf.encode( Encoding )
     getincrementaldecoder = codecs.getincrementaldecoder( Encoding )
+
 else:
     decode, encode = NullCodec.decode, NullCodec.encode
 
@@ -54,11 +56,16 @@ else:
         return NullCodec
 
 try:
-    # pylint: disable=import-error
-    oldpexpect = None
-    import pexpect as oldpexpect
+    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
 
-    # pylint: enable=import-error
     class Pexpect( object ):
         "Custom pexpect that is compatible with str"
         @staticmethod
@@ -97,11 +104,12 @@ def oldQuietRun( *cmd ):
         cmd = cmd[ 0 ]
         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:
@@ -119,6 +127,8 @@ 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
@@ -142,6 +152,7 @@ def errRun( *cmd, **kwargs ):
     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
@@ -186,7 +197,8 @@ def errRun( *cmd, **kwargs ):
     if stderr == PIPE:
         popen.stderr.close()
     debug( out, err, returncode )
-    return out, err, returncode
+    return CmdResult( out, err, returncode )
+
 # pylint: enable=too-many-branches
 
 def errFail( *cmd, **kwargs ):
@@ -195,11 +207,11 @@ 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
 
 def which(cmd, **kwargs ):
     "Run a command and return merged stdout and stderr"
@@ -537,18 +549,25 @@ def fixLimits():
               "Mininet's performance may be affected.\n" )
     # pylint: enable=broad-except
 
-
-def mountCgroups():
-    "Make sure cgroups file system is mounted"
-    mounts = quietRun( 'grep cgroup /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 )"
@@ -697,3 +716,26 @@ def waitListening( client=None, server='127.0.0.1', port=80, timeout=None ):
         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

@@ -24,6 +24,9 @@
 #include <sched.h>
 #include <ctype.h>
 #include <sys/mount.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <dirent.h>
 
 #if !defined(VERSION)
 #define VERSION "(devel)"
@@ -96,18 +99,26 @@ int main(int argc, char *argv[])
 {
     int c;
     int fd;
+    DIR *dir;
+    struct dirent *de;
     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)
         switch(c) {
         case 'c':
             /* close file descriptors except stdin/out/error */
-            for (fd = getdtablesize(); fd > 2; fd--)
-                close(fd);
+            if ((dir = opendir("/proc/self/fd"))) {
+                while ((de = readdir(dir)))
+                    if ((fd = atoi(de->d_name)) > 2)
+                        close(fd);
+            }
+            /* fall back to old method if needed */
+            else for (fd = getdtablesize(); fd > 2; fd--)
+                     close(fd);
             break;
         case 'd':
             /* detach from tty */

util/doxify.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/python2
 
 """
 Convert simple documentation to epydoc/pydoctor-compatible markup
@@ -83,7 +83,3 @@ if __name__ == '__main__':
     infile.close()
     os.close( outfid )
     call( [ 'doxypy', outname ] )
-
-
-
-

util/install.sh

@@ -164,7 +164,9 @@ function mn_deps {
     if [ "$DIST" = "Fedora" -o "$DIST" = "RedHatEnterpriseServer" ]; then
         $install gcc make socat psmisc xterm openssh-clients iperf \
             iproute telnet python-setuptools libcgroup-tools \
-            ethtool help2man pyflakes pylint python-pep8 python-pexpect
+            ethtool help2man net-tools
+        $install ${PYPKG}-pyflakes pylint ${PYPKG}-pep8-naming
+            ${PYPKG}-pexpect
     elif [ "$DIST" = "SUSE LINUX"  ]; then
 		$install gcc make socat psmisc xterm openssh iperf \
 			iproute telnet ${PYPKG}-setuptools libcgroup-tools \
@@ -172,28 +174,39 @@ function mn_deps {
                         python-pep8 ${PYPKG}-pexpect ${PYPKG}-tk
     else  # Debian/Ubuntu
         pf=pyflakes
+        pep8=pep8
         # Starting around 20.04, installing pyflakes instead of pyflakes3
         # causes Python 2 to be installed, which is exactly NOT what we want.
-        if [ `expr $RELEASE '>=' 20.04` = "1" ]; then
+        if [ "$DIST" = "Ubuntu" -a `expr $RELEASE '>=' 20.04` = "1" ]; then
                 pf=pyflakes3
         fi
+        # Debian 11 "bullseye" renamed
+        # * pep8 to python3-pep8
+        # * pyflakes to pyflakes3
+        if [ "$DIST" = "Debian" -a `expr $RELEASE '>=' 11` = "1" ]; then
+                pf=pyflakes3
+                pep8=python3-pep8
+        fi
+
         $install gcc make socat psmisc xterm ssh iperf telnet \
-                 ethtool help2man $pf pylint pep8 \
-                 net-tools \
-                 ${PYPKG}-pexpect ${PYPKG}-tk
+                 ethtool help2man $pf pylint $pep8 \
+                 net-tools ${PYPKG}-tk
+
         # Install pip
         $install ${PYPKG}-pip || $install ${PYPKG}-pip-whl
         if ! ${PYTHON} -m pip -V; then
             if [ $PYTHON_VERSION == 2 ]; then
-                wget https://bootstrap.pypa.io/2.6/get-pip.py
+                wget https://bootstrap.pypa.io/pip/2.7/get-pip.py
             else
                 wget https://bootstrap.pypa.io/get-pip.py
             fi
             sudo ${PYTHON} get-pip.py
             rm get-pip.py
         fi
+       ${python} -m pip install pexpect
         $install iproute2 || $install iproute
         $install cgroup-tools || $install cgroup-bin
+        $install cgroupfs-mount
     fi
 
     echo "Installing Mininet core"
@@ -205,10 +218,11 @@ function mn_deps {
 # Install Mininet documentation dependencies
 function mn_doc {
     echo "Installing Mininet documentation dependencies"
-    $install doxygen doxypy texlive-fonts-recommended
+    $install doxygen texlive-fonts-recommended
     if ! $install doxygen-latex; then
         echo "doxygen-latex not needed"
     fi
+    sudo pip2 install doxypy
 }
 
 # The following will cause a full OF install, covering:
@@ -228,7 +242,7 @@ function of {
     fi
     # was: git clone git://openflowswitch.org/openflow.git
     # Use our own fork on github for now:
-    git clone git://github.com/mininet/openflow
+    git clone https://github.com/mininet/openflow
     cd $BUILD_DIR/openflow
 
     # Patch controller to handle more than 16 switches
@@ -407,7 +421,10 @@ function ovs {
     echo "Installing Open vSwitch..."
 
     if [ "$DIST" = "Fedora" -o "$DIST" = "RedHatEnterpriseServer" ]; then
-        $install openvswitch openvswitch-controller
+        $install openvswitch
+        if ! $install openvswitch-controller; then
+            echo "openvswitch-controller not installed"
+        fi
         return
     fi
 
@@ -492,7 +509,7 @@ function ivs {
 
     # Install IVS from source
     cd $BUILD_DIR
-    git clone git://github.com/floodlight/ivs $IVS_SRC
+    git clone https://github.com/floodlight/ivs $IVS_SRC
     cd $IVS_SRC
     git submodule update --init
     make
@@ -512,7 +529,7 @@ function ryu {
 
     # fetch RYU
     cd $BUILD_DIR/
-    git clone git://github.com/osrg/ryu.git ryu
+    git clone https://github.com/osrg/ryu.git ryu
     cd ryu
 
     # install ryu
@@ -623,7 +640,7 @@ function oftest {
 
     # Install oftest:
     cd $BUILD_DIR/
-    git clone git://github.com/floodlight/oftest
+    git clone https://github.com/floodlight/oftest
 }
 
 # Install cbench
@@ -640,7 +657,7 @@ function cbench {
     cd $BUILD_DIR/
     # was:  git clone git://gitosis.stanford.edu/oflops.git
     # Use our own fork on github for now:
-    git clone git://github.com/mininet/oflops
+    git clone https://github.com/mininet/oflops
     cd oflops
     sh boot.sh || true # possible error in autoreconf, so run twice
     sh boot.sh
@@ -791,7 +808,7 @@ function vm_clean {
     echo 'Removing SSH keys from /etc/ssh/'
     sudo rm -f /etc/ssh/*key*
     if [ ! -e /etc/rc.local ]; then
-        echo '#!/usr/bin/bash' | sudo tee /etc/rc.local
+        echo '#!/bin/bash' | sudo tee /etc/rc.local
         sudo chmod +x /etc/rc.local
     fi
     if ! grep mininet /etc/rc.local >& /dev/null; then

util/unpep8

@@ -1,7 +1,7 @@
-#!/usr/bin/python
+#!/usr/bin/python2
 
 """
-Translate from PEP8 Python style to Mininet (i.e. Arista-like) 
+Translate from PEP8 Python style to Mininet (i.e. Arista-like)
 Python style
 
 usage: unpep8 < old.py > new.py
@@ -51,7 +51,7 @@ def fixUnderscoreTriplet( match ):
 def reinstateCapWords( text ):
    underscoreTriplet = re.compile( r'[A-Za-z0-9]_[A-Za-z0-9]' )
    return underscoreTriplet.sub( fixUnderscoreTriplet, text )
- 
+
 def replaceTripleApostrophes( text ):
    "Replace triple apostrophes with triple quotes."
    return text.replace( "'''", '"""')
@@ -60,7 +60,7 @@ def simplifyTripleQuotes( text ):
    "Fix single-line doc strings."
    r = re.compile( r'"""([^\"\n]+)"""' )
    return r.sub( r'"\1"', text )
-   
+
 def insertExtraSpaces( text ):
    "Insert extra spaces inside of parentheses and brackets/curly braces."
    lparen = re.compile( r'\((?![\s\)])' )
@@ -76,9 +76,9 @@ def insertExtraSpaces( text ):
    lcurly = re.compile( r'\{(?![\s\}])' )
    text = lcurly.sub( r'{ ', text )
    rcurly = re.compile( r'([^\s\{])(?=\})' )
-   text = rcurly.sub( r'\1 ', text)   
+   text = rcurly.sub( r'\1 ', text)
    return text
-   
+
 def fixDoxygen( text ):
    """Translate @param foo to foo:, @return bar to returns: bar, and
       @author me to author: me"""
@@ -96,11 +96,11 @@ def removeCommentFirstBlankLine( text ):
    "Remove annoying blank lines after first line in comments."
    line = re.compile( r'("""[^\n]*\n)\s*\n', re.MULTILINE )
    return line.sub( r'\1', text )
-   
+
 def fixArgs( match, kwarg = re.compile( r'(\w+) = ' ) ):
    "Replace foo = bar with foo=bar."
    return kwarg.sub( r'\1=', match.group() )
-   
+
 def fixKeywords( text ):
    "Change keyword argumentsfrom foo = bar to foo=bar."
    args = re.compile( r'\(([^\)]+)\)', re.MULTILINE )
@@ -115,7 +115,7 @@ def fixKeywords( text ):
 def lineIter( text ):
    "Simple iterator over lines in text."
    for line in text.splitlines(): yield line
-   
+
 def stringIter( strList ):
    "Yield strings in strList."
    for s in strList: yield s
@@ -134,7 +134,7 @@ def restoreRegex( regex, old, new ):
 # This is a cheap hack, and it may not work 100%, since
 # it doesn't handle multiline strings.
 # However, it should be mostly harmless...
-   
+
 def restoreStrings( oldText, newText ):
    "Restore strings from oldText into newText, returning result."
    oldLines, newLines = lineIter( oldText ), lineIter( newText )
@@ -149,13 +149,13 @@ def restoreStrings( oldText, newText ):
       newLine = restoreRegex( tickStrings, oldLine, newLine )
       result += newLine + '\n'
    return result
-   
+
 # This might be slightly controversial, since it uses
 # three spaces to line up multiline comments. However,
 # I much prefer it. Limitations: if you have deeper
 # indents in comments, they will be eliminated. ;-(
 
-def fixComment( match, 
+def fixComment( match,
    indentExp=re.compile( r'\n([ ]*)(?=[^/s])', re.MULTILINE ),
    trailingQuotes=re.compile( r'\s+"""' ) ):
    "Re-indent comment, and join trailing quotes."
@@ -166,17 +166,17 @@ def fixComment( match,
    if len( originalIndent ) is not 0: indent += '   '
    comment = indentExp.sub( indent, comment )
    return originalIndent + trailingQuotes.sub( '"""', comment )
-   
+
 def fixCommentIndents( text ):
    "Fix multiline comment indentation."
    comments = re.compile( r'^([ ]*)("""[^"]*""")$', re.MULTILINE )
    return comments.sub( fixComment, text )
- 
+
 def removeBogusLinefeeds( text ):
    "Remove extra linefeeds at the end of single-line comments."
    bogusLfs = re.compile( r'"([^"\n]*)\n"', re.MULTILINE )
    return bogusLfs.sub( '"\1"', text)
-   
+
 def convertFromPep8( program ):
    oldProgram = program
    # Program text transforms

util/versioncheck.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 from subprocess import check_output as co
 from sys import exit, version_info

util/vm/build.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python2.7
+#!/usr/bin/python2
 
 """
 build.py: build a Mininet VM
@@ -954,7 +954,8 @@ def bootAndRun( image, prompt=Prompt, memory=1024, cpuCores=1, outputFile=None,
     log( '* Creating COW disk', cow )
     run( 'qemu-img create -f qcow2 -b %s %s' % ( image, cow ) )
     log( '* Extracting kernel and initrd' )
-    kernel, initrd, part = extractKernel( image, flavor=basename, imageDir=tmpdir )
+    kernel, initrd, partnum = extractKernel(
+        image, flavor=basename, imageDir=tmpdir )
     if LogToConsole:
         logfile = stdout
     else:
@@ -962,7 +963,7 @@ def bootAndRun( image, prompt=Prompt, memory=1024, cpuCores=1, outputFile=None,
                                       suffix='.testlog', delete=False )
     log( '* Logging VM output to', logfile.name )
     vm = boot( cow=cow, kernel=kernel, initrd=initrd, logfile=logfile,
-               memory=memory, cpuCores=cpuCores, part=part )
+               memory=memory, cpuCores=cpuCores, partnum=partnum )
     login( vm )
     log( '* Waiting for prompt after login' )
     vm.expect( prompt )

util/vm/install-mininet-vm.sh

@@ -25,7 +25,7 @@ if [ -e /etc/rc.local.backup ]; then
 fi
 # Fetch Mininet
 sudo apt-get -y -qq install git-core openssh-server
-git clone git://github.com/mininet/mininet
+git clone https://github.com/mininet/mininet
 # Optionally check out branch
 if [ "$1" != "" ]; then
     pushd mininet