tree.py

from mininet.net import Mininet
from mininet.node import RemoteController
from mininet.cli import CLI
from mininet.log import setLogLevel, info

def treeTopo():
    net = Mininet( controller=RemoteController )
    
    info( '*** Adding controller\n' )
    net.addController('c0')
    
    info( '*** Adding hosts\n' )
    h1 = net.addHost( 'h1', ip='10.0.0.1', mac='00:00:00:00:00:01' )
    h2 = net.addHost( 'h2', ip='10.0.0.2', mac='00:00:00:00:00:02' )
    h3 = net.addHost( 'h3', ip='10.0.0.3', mac='00:00:00:00:00:03' )
    h4 = net.addHost( 'h4', ip='10.0.0.4', mac='00:00:00:00:00:04' )
    h5 = net.addHost( 'h5', ip='10.0.0.5', mac='00:00:00:00:00:05' )
    h6 = net.addHost( 'h6', ip='10.0.0.6', mac='00:00:00:00:00:06' )
    h7 = net.addHost( 'h7', ip='10.0.0.7', mac='00:00:00:00:00:07' )
    h8 = net.addHost( 'h8', ip='10.0.0.8', mac='00:00:00:00:00:08' )

    info( '*** Adding switches\n' )
    s1 = net.addSwitch( 's1' )
    s2 = net.addSwitch( 's2' )
    s3 = net.addSwitch( 's3' )
    s4 = net.addSwitch( 's4' )
    s5 = net.addSwitch( 's5' )
    s6 = net.addSwitch( 's6' )
    s7 = net.addSwitch( 's7' )
    
    info( '*** Creating links\n' )
    net.addLink( h1, s3 )
    net.addLink( h2, s3 )
    net.addLink( h3, s4 )
    net.addLink( h4, s4 )
    net.addLink( h5, s6 )
    net.addLink( h6, s6 )
    net.addLink( h7, s7 )
    net.addLink( h8, s7 )
    
    root = s1
    layer1 = [s2,s5]
    layer2 = [s3,s4,s6,s7]
    
    for idx,l1 in enumerate(layer1):
        net.addLink( root,l1 )
        net.addLink( l1, layer2[2*idx] )
        net.addLink( l1, layer2[2*idx + 1] )
        
    info( '*** Starting network\n')
    net.start()
    
    info( '*** Running CLI\n' )
    CLI( net )
    
    info( '*** Stopping network' )
    net.stop()
    
if __name__ == '__main__':
    setLogLevel( 'info' )
    treeTopo()