Bob Lantz
ee15ce2243
Although we could use print() from __future__, this messes up scripts which use examples as modules. The simple, if not nicest for 2.7, solution is to use info(), output() and other mininet.log functions. The disadvantage is that we may have to adjust things if we change info() to add automatic newlines, but we can burn that bridge in Mininet 3.x.
85 lines
2.2 KiB
Python
Executable File
85 lines
2.2 KiB
Python
Executable File
#!/usr/bin/python
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"""
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multiping.py: monitor multiple sets of hosts using ping
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This demonstrates how one may send a simple shell script to
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multiple hosts and monitor their output interactively for a period=
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of time.
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"""
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from mininet.net import Mininet
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from mininet.node import Node
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from mininet.topo import SingleSwitchTopo
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from mininet.log import info, setLogLevel
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from select import poll, POLLIN
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from time import time
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def chunks( l, n ):
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"Divide list l into chunks of size n - thanks Stackoverflow"
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return [ l[ i: i + n ] for i in range( 0, len( l ), n ) ]
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def startpings( host, targetips ):
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"Tell host to repeatedly ping targets"
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targetips = ' '.join( targetips )
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# Simple ping loop
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cmd = ( 'while true; do '
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' for ip in %s; do ' % targetips +
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' echo -n %s "->" $ip ' % host.IP() +
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' `ping -c1 -w 1 $ip | grep packets` ;'
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' sleep 1;'
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' done; '
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'done &' )
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info( '*** Host %s (%s) will be pinging ips: %s\n' %
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( host.name, host.IP(), targetips ) )
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host.cmd( cmd )
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def multiping( netsize, chunksize, seconds):
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"Ping subsets of size chunksize in net of size netsize"
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# Create network and identify subnets
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topo = SingleSwitchTopo( netsize )
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net = Mininet( topo=topo )
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net.start()
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hosts = net.hosts
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subnets = chunks( hosts, chunksize )
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# Create polling object
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fds = [ host.stdout.fileno() for host in hosts ]
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poller = poll()
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for fd in fds:
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poller.register( fd, POLLIN )
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# Start pings
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for subnet in subnets:
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ips = [ host.IP() for host in subnet ]
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#adding bogus to generate packet loss
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ips.append( '10.0.0.200' )
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for host in subnet:
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startpings( host, ips )
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# Monitor output
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endTime = time() + seconds
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while time() < endTime:
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readable = poller.poll(1000)
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for fd, _mask in readable:
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node = Node.outToNode[ fd ]
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info( '%s:' % node.name, node.monitor().strip(), '\n' )
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# Stop pings
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for host in hosts:
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host.cmd( 'kill %while' )
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net.stop()
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if __name__ == '__main__':
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setLogLevel( 'info' )
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multiping( netsize=20, chunksize=4, seconds=10 )
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