Files
mininet/examples/popen.py
T
Bob Lantz 8ac077a721 Remove "from __future__ import print"
This was well-intentioned, but it causes more trouble
than it's worth.

Fixes #652
2016-08-08 15:28:52 -07:00

38 lines
1.0 KiB
Python
Executable File

#!/usr/bin/python
"""
This example monitors a number of hosts using host.popen() and
pmonitor()
"""
from mininet.net import Mininet
from mininet.node import CPULimitedHost
from mininet.topo import SingleSwitchTopo
from mininet.log import setLogLevel
from mininet.util import custom, pmonitor
def monitorhosts( hosts=5, sched='cfs' ):
"Start a bunch of pings and monitor them using popen"
mytopo = SingleSwitchTopo( hosts )
cpu = .5 / hosts
myhost = custom( CPULimitedHost, cpu=cpu, sched=sched )
net = Mininet( topo=mytopo, host=myhost )
net.start()
# Start a bunch of pings
popens = {}
last = net.hosts[ -1 ]
for host in net.hosts:
popens[ host ] = host.popen( "ping -c5 %s" % last.IP() )
last = host
# Monitor them and print output
for host, line in pmonitor( popens ):
if host:
print( "<%s>: %s" % ( host.name, line.strip() ) )
# Done
net.stop()
if __name__ == '__main__':
setLogLevel( 'info' )
monitorhosts( hosts=5 )