Let Mininet() explicitly delete links.

mininet/net.py

@@ -152,7 +152,8 @@ class Mininet( object ):
         self.hosts = []
         self.switches = []
         self.controllers = []
-
+        self.links = []
+        
         self.nameToNode = {}  # name to Node (Host/Switch) objects
 
         self.terms = []  # list of spawned xterm processes
@@ -252,7 +253,9 @@ class Mininet( object ):
         defaults.update( params )
         if not cls:
             cls = self.link
-        return cls( node1, node2, **defaults )
+        link = cls( node1, node2, **defaults )
+        self.links.append( link )
+        return link
 
     def configHosts( self ):
         "Configure a set of hosts."
@@ -372,15 +375,21 @@ class Mininet( object ):
         if self.terms:
             info( '*** Stopping %i terms\n' % len( self.terms ) )
             self.stopXterms()
-        info( '*** Stopping %i hosts\n' % len( self.hosts ) )
-        for host in self.hosts:
-            info( host.name + ' ' )
-            host.terminate()
         info( '\n' )
         info( '*** Stopping %i switches\n' % len( self.switches ) )
         for switch in self.switches:
             info( switch.name + ' ' )
-            switch.stop()
+            switch.stop( deleteIntfs=False )
+        info( '\n' )
+        info( '*** Removing %i links\n' % len( self.links ) )
+        for link in self.links:
+            info( '.' )
+            link.delete()
+        info( '\n' )
+        info( '*** Stopping %i hosts\n' % len( self.hosts ) )
+        for host in self.hosts:
+            info( host.name + ' ' )
+            host.terminate()
         info( '\n' )
         info( '*** Stopping %i controllers\n' % len( self.controllers ) )
         for controller in self.controllers:

mininet/node.py

@@ -49,6 +49,7 @@ import re
 import signal
 import select
 from subprocess import Popen, PIPE, STDOUT
+from sys import stdout
 
 from mininet.log import info, error, warn, debug
 from mininet.util import ( quietRun, errRun, errFail, moveIntf, isShellBuiltin,
@@ -405,6 +406,7 @@ class Node( object ):
         for intf in self.intfs.values():
             intf.delete()
             info( '.' )
+            stdout.flush()
 
     # Routing support
 
@@ -840,11 +842,12 @@ class UserSwitch( Switch ):
                   ' --fail=closed ' + self.opts +
                   ' 1> ' + ofplog + ' 2>' + ofplog + ' &' )
 
-    def stop( self ):
+    def stop( self, deleteIntfs=True ):
         "Stop OpenFlow reference user datapath."
         self.cmd( 'kill %ofdatapath' )
         self.cmd( 'kill %ofprotocol' )
-        self.deleteIntfs()
+        if deleteIntfs:
+            self.deleteIntfs()
 
 
 class OVSLegacyKernelSwitch( Switch ):
@@ -891,11 +894,12 @@ class OVSLegacyKernelSwitch( Switch ):
                   ' 1>' + ofplog + ' 2>' + ofplog + '&' )
         self.execed = False
 
-    def stop( self ):
+    def stop( self, deleteIntfs=True ):
         "Terminate kernel datapath."
         quietRun( 'ovs-dpctl del-dp ' + self.dp )
         self.cmd( 'kill %ovs-openflowd' )
-        self.deleteIntfs()
+        if deleteIntfs:
+            self.deleteIntfs()
 
 
 class OVSSwitch( Switch ):
@@ -974,10 +978,11 @@ class OVSSwitch( Switch ):
             clist += ' ptcp:%s' % self.listenPort
         self.cmd( 'ovs-vsctl set-controller', self, clist )
 
-    def stop( self ):
-        "Terminate OVS switch."
+    def stop( self, deleteIntfs=True ):
+        "Stop OVS switch."
         self.cmd( 'ovs-vsctl del-br', self )
-        self.deleteIntfs()
+        if deleteIntfs:
+            self.deleteIntfs()
 
 OVSKernelSwitch = OVSSwitch