When setting up RIP2?

Beany

Afternoon,

got a question on activating RIP2.

I know it's a simple process, router rip, version 2 and network commands.

What i cant get my head around is the network command. Can someone explain this to me with examples? how to know which address to add looking at connected interfaces addresses? classful?

thanks

networker050184

The network command includes interfaces into the process. If the interface IP address falls within the range of the network command the interface is added to the protocol and the address/mask configured on the interface is advertised.

Beany

Please see attached image.

can someone explain to me why line 2 needs changing?

FloOz

Well from looking at the exhibit it doesn't look like router B has a interface in the 192.168.0.0 network range. Router A does so it would require a network 192.168.0.0 command.

The network 10.0.0.0 on router B would encompass all of router B's interface and advertise them. So no other network commands would be necessary.

Beany

but adding 192.168.0.0 still wouldnt work?

FloOz

Adding 192.168.0.0 won't do anything when configured on router B unless router B had some interfaces in the 192.168.0.0 range. That is why the answer is line 2 should be changed. Its because it is not needed

networker050184

What is the classful network range for the link between router A and B? Now look at the network command in line 2. Do these two match?

dover

Router B's serial interface to router A is on the 192.168.50.64/26 network. So line two should be: network 192.168.50.0 so that it is included in the RIP topology and accept and advertise networks in that range to other RIP routers.

If (on router you use the command network 192.168.0.0 Router B will never get/accept routes from Router A

You will see nothing in a debug ip rip. Once you change the statement to network 192.168.50.0 (on Router
you will see

*Mar 1 00:21:35.711: RIP: build flash update entries
*Mar 1 00:21:35.711: 192.168.50.0/24 via 0.0.0.0, metric 1, tag 0
*Mar 1 00:21:35.715: RIP: sending v2 flash update to 224.0.0.9 via Ethernet0 (192.168.50.66)


Then you'll see your learned RIP route with sho ip route

10.0.0.0/27 is subnetted, 1 subnets
C 10.82.113.0 is directly connected, FastEthernet0
192.168.50.0/26 is subnetted, 2 subnets
C 192.168.50.64 is directly connected, Ethernet0
R 192.168.50.128 [120/1] via 192.168.50.65, 00:00:15, Ethernet0

I think the question is getting at seeing if you understand the RIP network statement has two functions: activate the interfaces for RIP and announce networks in the major - classful - network (i.e. 10.0.0.0 or 192.168.50.0).

***EDIT---What Networker said above ^. I tend to bang out configs instead of replying with thought-provoking help.

atorven

To expand on what Flo0z is saying, you would also need to add a network statement matching that interface connecting to Router B, remember RIP cares about classful networks.