FatTree_4.py

"""Custom topology example
Two directly connected switches plus a host for each switch:
   host --- switch --- switch --- host
Adding the 'topos' dict with a key/value pair to generate our newly defined
topology enables one to pass in '--topo=mytopo' from the command line.
"""

from mininet.topo import Topo

class MyTopo( Topo ):

    def build( self ):
        "Create custom topo."

        # Add hosts
        h1 = self.addHost( 'h1' )
        h2 = self.addHost( 'h2' )
        h3 = self.addHost( 'h3' )
        h4 = self.addHost( 'h4' )
        h5 = self.addHost( 'h5' )
        h6 = self.addHost( 'h6' )
        h7 = self.addHost( 'h7' )
        h8 = self.addHost( 'h8' )
        # Add Switches
        s1 = self.addSwitch( 's1' )
        s2 = self.addSwitch( 's2' )
        s3 = self.addSwitch( 's3' )
        s4 = self.addSwitch( 's4' )
        s5 = self.addSwitch( 's5' )
        s6 = self.addSwitch( 's6' 

        # Add links hosts--switches
        self.addLink(h1, s3)
        self.addLink(h2, s3)
        self.addLink(h3, s4)
        self.addLink(h4, s4)
        self.addLink(h5, s5)
        self.addLink(h6, s5)
        self.addLink(h7, s6)
        self.addLink(h8, s6)

        #add links s1--All Switches
        self.addLink(s1, s3)
        self.addLink(s1, s4)
        self.addLink(s1, s5)
        self.addLink(s1, s6)
        #addlinks s2--All Switches
        self.addLink(s2, s3)
        self.addLink(s2, s4)
        self.addLink(s2, s5)
        self.addLink(s2, s6)

topos = { 'mytopo': ( lambda: MyTopo() ) }