Enabling RIP
To configure RIP routing, just turn on the protocol with the router rip command and tell
the RIP routing protocol which networks to advertise. Table 3.10 shows the basic configuration
of enabling RIP:
Here’s an example:
Router#config t
Router(config)#router rip
Router(config-router)#network 10.0.0.0
That’s it. Two or three commands, and you’re done—that sure makes your job a lot easier
than when using static routes, doesn’t it? However, keep in mind the extra router CPU process
and bandwidth you’re consuming.
Notice I didn’t type subnets, only the classful network address (all subnet bits and host bits
off!). It is the job of the routing protocol to find the subnets and populate the routing tables.
Since you have no router buddies running RIP, you won’t see any RIP routes in the routing
table yet.
Remember that RIP uses the classful address when configuring the network address.
Because of this, all subnet masks must be the same on all devices in the network (this is called
classful routing).
To clarify this, let’s say you’re using a Class B network address of 172.16.0.0/24 with subnets
172.16.10.0, 172.16.20.0, and 172.16.30.0. You would type only the classful network
address of 172.16.0.0 and let RIP find the subnets and place them in the routing table.
TABLE 3 . 1 0 RIP Commands
Command Meaning
router rip Starts and enable a RIP routing process
network Configures a network to advertise and enable
interfaces into the routing process