topology.py

from mininet.topo import Topo
from mininet.net import Mininet
from mininet.node import RemoteController
from mininet.cli import CLI


# Create a custom topology
class MyTopology(Topo):
    def build(self):

        # Add switches
        s1 = self.addSwitch('s1')
        s2 = self.addSwitch('s2')
        # Add hosts
        h1 = self.addHost('h1', mac ="00:00:00:00:00:01")
        h2 = self.addHost('h2', mac ="00:00:00:00:00:02")
        h3 = self.addHost('h3', mac ="00:00:00:00:00:03")
        h4 = self.addHost('h4', mac ="00:00:00:00:00:04")
        h5 = self.addHost('h5', mac ="00:00:00:00:00:05")

        # Connect hosts to the switch
        self.addLink(h1, s1)
        self.addLink(h2, s1)
        self.addLink(h3, s1)
        self.addLink(s1, s2)
        self.addLink(s2, h4)
        self.addLink(s2, h5)


if __name__ == '__main__':
    topo = MyTopology()
    c1 = RemoteController('c1', ip='127.0.0.1')
    net = Mininet(topo=topo, controller=c1)
    net.start()
    CLI(net)
    net.stop()