Getting started

To start your network, you need to do two things:

1. Creating a topology
2. Running the network

Topology creation

To create a new topology, we need to declare a class that extends IPTopo.

from ipmininet.iptopo import IPTopo

class MyTopology(IPTopo):
    pass

Then we extend in its build method to add switches, hosts, routers and links between the nodes.

from ipmininet.iptopo import IPTopo

class MyTopology(IPTopo):

    def build(self, *args, **kwargs):

        r1 = self.addRouter("r1")
        r2 = self.addRouter("r2")
        # Helper to create several routers in one function call
        r3, r4, r5 = self.addRouters("r3", "r4", "r5")

        s1 = self.addSwitch("s1")
        s2 = self.addSwitch("s2")

        h1 = self.addHost("h1")
        h2 = self.addHost("h2")

        self.addLink(r1, r2)
        # Helper to create several links in one function call
        self.addLinks((s1, r1), (h1, s1), (s2, r2), (h2, s2), (r2, r3),
                      (r3, r4), (r4, r5))

        super().build(*args, **kwargs)

We can add daemons to the routers and hosts as well.

from ipmininet.iptopo import IPTopo
from ipmininet.router.config import SSHd
from ipmininet.host.config import Named

class MyTopology(IPTopo):

    def build(self, *args, **kwargs):

        r1 = self.addRouter("r1")
        r1.addDaemon(SSHd)

        h1 = self.addHost("h1")
        h1.addDaemon(Named)

        # [...]

        super().build(*args, **kwargs)

By default, OSPF and OSPF6 are launched on each router. This means that your network has basic routing working by default. To change that, we have to modify the router configuration class.

from ipmininet.iptopo import IPTopo
from ipmininet.router.config import SSHd, RouterConfig

class MyTopology(IPTopo):

    def build(self, *args, **kwargs):

        r1 = self.addRouter("r1", config=RouterConfig)
        r1.addDaemon(SSHd)

        # [...]

        super().build(*args, **kwargs)

We can customize the daemons configuration by passing options to them. In the following code snippet, we change the hello interval of the OSPF daemon. You can find the configuration options in Configuring daemons

from ipmininet.iptopo import IPTopo
from ipmininet.router.config import OSPF, RouterConfig

class MyTopology(IPTopo):

    def build(self, *args, **kwargs):

        r1 = self.addRouter("r1", config=RouterConfig)
        r1.addDaemon(OSPF, hello_int=1)

        # [...]

        super().build(*args, **kwargs)

Network run

We run the topology by using the following code. The IPCLI object creates a extended Mininet CLI. More details can be found in Command-Line interface As for Mininet, IPMininet networks need root access to be executed.

from ipmininet.ipnet import IPNet
from ipmininet.cli import IPCLI

net = IPNet(topo=MyTopology())
try:
    net.start()
    IPCLI(net)
finally:
    net.stop()

By default, all the generated configuration files for each daemon are removed. You can prevent this behavior by setting ipmininet.DEBUG_FLAG to True before stopping the network.

IPMininet network cleaning

If you forget to clean your network with net.stop() in your script, your machine can will have ghost daemon process and uncleaned network namespaces. This can also happen if IPMininet crashes. In both cases, you have to clean it up with the following command:

sudo python -m ipmininet.clean

Mininet compatibility

IPMininet is an upper layer above Mininet. Therefore, everything that works in Mininet, also works in IPMininet. Feel free to consult the Mininet documentation as well.

Additional helpers functions

You can pass parameters to addLinks and addRouters helpers. These parameters can be common to all links and routers but they can also be specific:

from ipmininet.iptopo import IPTopo
from ipmininet.router.config import RouterConfig

class MyTopology(IPTopo):

    def build(self, *args, **kwargs):

        # The config parameter is set to RouterConfig for every router
        r1, r2 = self.addRouters("r1", "r2", config=RouterConfig)
        # The config parameter is set only for "r3"
        r3, r4, r5 = self.addRouters(("r3", {"config": RouterConfig}),
                                     "r4", "r5")

        s1 = self.addSwitch("s1")
        s2 = self.addSwitch("s2")

        h1 = self.addHost("h1")
        h2 = self.addHost("h2")

        # 'igp_metric' parameter is set to 5 for all the links while
        # the 'ip' parameter is set only for the link between 'r1' and 'r2'
        self.addLinks((r1, r2, {'params1': {'ip': ("2042:12::1/64", "10.12.0.1/24")},
                                'params2': {'ip': ("2042:12::2/64", "10.12.0.2/24")}}),
                      (s1, r1), (h1, s1), (s2, r2), (h2, s2),
                      (r2, r3), (r3, r4), (r4, r5), igp_metric=5)

        super().build(*args, **kwargs)