To start your network, you need to do two things:
- Creating a topology
- Running the network
To create a new topology, we need to declare a class
that extends IPTopo.
from ipmininet.iptopo import IPTopo
class MyTopology(IPTopo):
passThen we extend in its build method to add switches, hosts, routers and links between the nodes.
.. testcode:: topo creation
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.
.. testcode:: topo creation addDaemon
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.
.. testcode:: topo creation config param
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 :ref:`Configuring daemons`
.. testcode:: topo creation addDeamon params
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)
We run the topology by using the following code. The IPCLI object creates a extended Mininet CLI. More details can be found in :ref:`Command-Line interface` As for Mininet, IPMininet networks need root access to be executed.
.. testcode:: network run
:hide:
mocking = MockStdIn()
mocking.close_on_start_cli()
from ipmininet.iptopo import IPTopo
class MyTopology(IPTopo):
def build(self, *args, **kwargs):
r1 = self.addRouter("r1")
r2 = self.addRouter("r2")
s1 = self.addSwitch("s1")
s2 = self.addSwitch("s2")
h1 = self.addHost("h1")
h2 = self.addHost("h2")
self.addLink(r1, r2)
self.addLink(s1, r1)
self.addLink(h1, s1)
self.addLink(s2, r2)
self.addLink(h2, s2)
super().build(*args, **kwargs)
.. testcode:: network run
from ipmininet.ipnet import IPNet
from ipmininet.cli import IPCLI
net = IPNet(topo=MyTopology())
try:
net.start()
IPCLI(net)
finally:
net.stop()
.. testoutput:: network run
:hide:
:options: +ELLIPSIS
mininet> ...
.. testcleanup:: network run
mocking.clean()
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.
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.cleanIPMininet 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.
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:
.. testcode:: topo creation addLinks addRouters
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)
.. testsetup:: *
from ipmininet.clean import cleanup
cleanup(level='warning')
.. testcode:: topo creation,topo creation addDaemon,topo creation config param,topo creation addDeamon params,topo creation addLinks addRouters
:hide:
try:
MyTopology
except NameError:
MyTopology = None
if MyTopology is not None:
from ipmininet.ipnet import IPNet
net = IPNet(topo=MyTopology())
net.start()
.. testcleanup:: topo creation,topo creation addDaemon,topo creation config param,topo creation addDeamon params,topo creation addLinks addRouters
try:
net
except NameError:
net = None
if net is not None:
net.stop()