network command in RIP

R1 has two networks directly connected
192.168.10.0
192.168.20.0

R2 has two networks directly connected
192.168.10.0
192.168.30.0

When configure RIP, I only have "network 192.168.10.0" for both routers, and then R1 still does not learn 192.168.30.0 and R2 does not learn 192.168.20.0.

I knew this is expected, but why? For R1, I thought it should update R2 its 192.168.20.0 whatsoever since that route is in the routing table even no RIP.

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Comments

EdTheLad

You only send updates of whats in the RIP database, to add routes to the database use either network or redistribute command.

TheNewITGuy

network statement is going to define that the interface configured in that range will participate in the RIP instance, it does not specify to "advertise" as it does in bgp. You will want to use redistribute connected and no auto-summary within your rip configuration to allow your neighbor to learn the routes.

EdTheLad

TheNewITGuy wrote: »

network statement is going to define that the interface configured in that range will participate in the RIP instance, it does not specify to "advertise" as it does in bgp. You will want to use redistribute connected and no auto-summary within your rip configuration to allow your neighbor to learn the routes.

The network statement defines which interfaces will participate in RIP and also which interfaces get advertised in RIP. "no auto-summary" isn't required in this example. If 192.168.20.0 and 192.168.30.0 are addresses on connected interfaces its better to use the network statement along with passive interface rather than redistribution.

TheNewITGuy

If R1 is connected to R2 and the neighboring interfaces are 20.0 and 30.0 why are you gonna use network to have the other interface participate? The non-peer'd interfaces have no need to be participating, they just need to be distributed into the routing protocol and NOT send/receive updates.

I understand if he puts the other interfaces via network he'll advertise those because they are interfaces

no auto-summary may not apply in this situation, but is good practice for the OP. I am pretty sure it wont come down to just connected and Class C addresses that he wishes to advertise in rip or any other IGP

Remember these Network Statements are meant to identify which interfaces willl participate in the Routing Protocol Process. Some people think that they mean which networks will be advertised, which is not true. So the more specific you make the Network statement with the mask, the more control you have over which interfaces participate.

networker050184

The network command means both that the interface will participate in sending routing updates and the network on the interface will be advertised into the protocol. If you want a network advertised into the protocol and and not send updates use the passive-interface command. Redistributing leads to external routes which may not always be the best way to go.

johnifanx98

EdTheLad wrote: »

You only send updates of whats in the RIP database, to add routes to the database use either network or redistribute command.

Is there a way to verify the content of RIP database? It seems like the "show ip route" is not by default part of RIP database...

Dieg0M

I believe show ip rip database.

johnifanx98

Dieg0M wrote: »

I believe show ip rip database.

Thanks. Not every directly connected network shows up unless running "network" on it. This is a great command to help understand RIP...