+linuxrouter.py: Example network with Linux IP router
+This example converts a Node into a router using IP forwarding
+already built into Linux.
+The topology contains a router with three IP subnets:
+ - 192.168.1.0/24 (interface IP: 192.168.1.1)
+ - 172.16.0.0/12 (interface IP: 172.16.0.1)
+ - 10.0.0.0/8 (interface IP: 10.0.0.1)
+ It also contains three hosts, one in each subnet:
+ - h1 (IP: 192.168.1.100)
+ - h2 (IP: 172.16.0.100)
+ Routing entries can be added to the routing tables of the
+ hosts or router using the "ip route add" or "route add" command.
+ See the man pages for more details.
+from mininet.topo import Topo
+from mininet.net import Mininet
+from mininet.node import Node
+from mininet.log import setLogLevel, info
+from mininet.cli import CLI
+from mininet.util import irange
+class LinuxRouter( Node ):
+ "A Node with IP forwarding enabled."
+ def config( self, **params ):
+ super( LinuxRouter, self).config( **params )
+ # Enable forwarding on the router
+ #self.cmd( 'sysctl net.ipv4.ip_forward=1' )
+ #self.cmd( 'sysctl net.ipv4.ip_forward=0' )
+ super( LinuxRouter, self ).terminate()
+class NetworkTopo( Topo ):
+ "A simple topology of a router with three subnets (one host in each)."
+ def build( self, n=2, h=1, **opts ):
+ router = self.addNode( 'router', cls=LinuxRouter, ip='10.0.10.1/24' , inNamespace=False)
+ host1 = self.addHost( 'host1', ip='10.0.10.2/24', defaultRoute='via 10.0.10.1' )
+ host2 = self.addHost( 'host2', ip='10.0.11.2/24', defaultRoute='via 10.0.11.1' )
+ server = self.addHost( 'server', ip='10.0.12.2/24')
+ self.addLink( host1, router, intfName2='router-eth1', params2={ 'ip' : '10.0.10.1/24' } )
+ self.addLink( host2, router, intfName2='router-eth2', params2={ 'ip' : '10.0.11.1/24' } )
+ self.addLink( server, router, intfName2='router-eth3', params2={ 'ip' : '10.0.12.1/24' } )
+ self.addLink( server, router,
+ intfName1='server-eth1', params1={ 'ip' : '10.0.13.2/24' },
+ intfName2='router-eth4', params2={ 'ip' : '10.0.13.1/24' })
+ net = Mininet( topo=topo, controller=None ) # no controller needed
+ net[ 'server' ].cmd( 'ifconfig lo:0 11.0.14.1/24 up')
+ net[ 'server' ].cmd( 'ip route add 10.0.10.0/24 via 10.0.12.1')
+ #net[ 'server' ].cmd( 'ip route add 10.0.11.0/24 via 10.0.12.1')
+ net[ 'server' ].cmd( 'ip route add 10.0.11.0/24 via 10.0.13.1')
+ #net[ 'router' ].cmd( 'route add -net 11.0.14.0/24 dev router-eth3')
+ info( '*** Add traffic classification rules to select different routing table\n' )
+ net[ 'router' ].cmd( 'ip rule del from 10.0.10.0/24 lookup net1_table' )
+ net[ 'router' ].cmd( 'ip rule add from 10.0.10.0/24 lookup net1_table' )
+ net[ 'router' ].cmd( 'ip rule del from 10.0.11.0/24 lookup net2_table' )
+ net[ 'router' ].cmd( 'ip rule add from 10.0.11.0/24 lookup net2_table' )
+ print net[ 'router' ].cmd( 'ip rule list' )
+ info( '*** Add routing Tables\n' )
+ net[ 'router' ].cmd( 'grep net1_table /etc/iproute2/rt_tables || echo "101 net1_table">> /etc/iproute2/rt_tables' )
+ net[ 'router' ].cmd( 'grep net2_table /etc/iproute2/rt_tables || echo "102 net2_table">> /etc/iproute2/rt_tables' )
+ print net[ 'router' ].cmd( 'egrep net.*_table /etc/iproute2/rt_tables' )
+ info( '*** Add routes to the routing tables\n' )
+ net[ 'router' ].cmd( 'ip route add 11.0.14.0/24 via 10.0.12.2 table net1_table')
+ net[ 'router' ].cmd( 'ip route add 11.0.14.0/24 via 10.0.13.2 table net2_table')
+ print net[ 'router' ].cmd( 'ip route list table net1_table')
+ print net[ 'router' ].cmd( 'ip route list table net2_table')
+ info( '*** Routing Table on Router\n' )
+ print net[ 'router' ].cmd( 'route -n|grep router' )
+ info( '*** Routing Table on Server\n' )
+ print net[ 'server' ].cmd( 'route -n' )
+if __name__ == '__main__':
