NePA TesT: Community Network Emulator

"""

Mininet Cleanup

author: Bob Lantz (rlantz@cs.stanford.edu)

Unfortunately, Mininet and OpenFlow (and the Linux kernel)

don't always clean up properly after themselves. Until they do

(or until cleanup functionality is integrated into the Python

code), this script may be used to get rid of unwanted garbage.

It may also get rid of 'false positives', but hopefully

nothing irreplaceable!

"""

from subprocess import ( Popen, PIPE, check_output as co,

                         CalledProcessError )

import time

from mininet.log import info

from mininet.term import cleanUpScreens

def sh( cmd ):

    "Print a command and send it to the shell"

    info( cmd + '\n' )

    return Popen( [ '/bin/sh', '-c', cmd ], stdout=PIPE ).communicate()[ 0 ]

def killprocs( pattern ):

    "Reliably terminate processes matching a pattern (including args)"

    sh( 'pkill -9 -f %s' % pattern )

    # Make sure they are gone

    while True:

        try:

            pids = co( [ 'pgrep', '-f', pattern ] )

        except CalledProcessError:

            pids = ''

        if pids:

            sh( 'pkill -9 -f %s' % pattern )

            time.sleep( .5 )

        else:

            break

class Cleanup( object ):

    "Wrapper for cleanup()"

    callbacks = []

    @classmethod

    def cleanup( cls):

        """Clean up junk which might be left over from old runs;

           do fast stuff before slow dp and link removal!"""

        info( "*** Removing excess controllers/ofprotocols/ofdatapaths/"

              "pings/noxes\n" )

        zombies = 'controller ofprotocol ofdatapath ping nox_core lt-nox_core '

        zombies += 'ovs-openflowd ovs-controller udpbwtest mnexec ivs'

        # Note: real zombie processes can't actually be killed, since they

        # are already (un)dead. Then again,

        # you can't connect to them either, so they're mostly harmless.

        # Send SIGTERM first to give processes a chance to shutdown cleanly.

        sh( 'killall ' + zombies + ' 2> /dev/null' )

        time.sleep( 1 )

        sh( 'killall -9 ' + zombies + ' 2> /dev/null' )

        # And kill off sudo mnexec

        sh( 'pkill -9 -f "sudo mnexec"')

        info( "*** Removing junk from /tmp\n" )

        sh( 'rm -f /tmp/vconn* /tmp/vlogs* /tmp/*.out /tmp/*.log' )

        info( "*** Removing old X11 tunnels\n" )

        cleanUpScreens()

        info( "*** Removing excess kernel datapaths\n" )

        dps = sh( "ps ax | egrep -o 'dp[0-9]+' | sed 's/dp/nl:/'"

                  ).splitlines()

        for dp in dps:

            if dp:

                sh( 'dpctl deldp ' + dp )

        info( "***  Removing OVS datapaths\n" )

        dps = sh("ovs-vsctl --timeout=1 list-br").strip().splitlines()

        if dps:

            sh( "ovs-vsctl " + " -- ".join( "--if-exists del-br " + dp

                                            for dp in dps if dp ) )

        # And in case the above didn't work...

        dps = sh( "ovs-vsctl --timeout=1 list-br" ).strip().splitlines()

        for dp in dps:

            sh( 'ovs-vsctl del-br ' + dp )

        info( "*** Removing all links of the pattern foo-ethX\n" )

        links = sh( "ip link show | "

                    "egrep -o '([-_.[:alnum:]]+-eth[[:digit:]]+)'"

                    ).splitlines()

        # Delete blocks of links

        n = 1000  # chunk size

        for i in xrange( 0, len( links ), n ):

            cmd = ';'.join( 'ip link del %s' % link

                             for link in links[ i : i + n ] )

            sh( '( %s ) 2> /dev/null' % cmd )

        if 'tap9' in sh( 'ip link show' ):

            info( "*** Removing tap9 - assuming it's from cluster edition\n" )

            sh( 'ip link del tap9' )

        info( "*** Killing stale mininet node processes\n" )

        killprocs( 'mininet:' )

        info( "*** Shutting down stale tunnels\n" )

        killprocs( 'Tunnel=Ethernet' )

        killprocs( '.ssh/mn')

        sh( 'rm -f ~/.ssh/mn/*' )

        # Call any additional cleanup code if necessary

        for callback in cls.callbacks:

            callback()

        info( "*** Cleanup complete.\n" )

    @classmethod

    def addCleanupCallback( cls, callback ):

        "Add cleanup callback"

        if callback not in cls.callbacks:

            cls.callbacks.append( callback )

cleanup = Cleanup.cleanup

addCleanupCallback = Cleanup.addCleanupCallback