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New Member

RIP, supernet


Could you please give me a note on the following:

We want to use RIP over an interface, which has a netmask that is shorter than the classful mask.

The router doesn't send RIP packets out on this interface, but I can see the interface in the output of "show ip protocols".

Thanks, Attila


Re: RIP, supernet

The router will not advertise it's outgoing interfaces route to its neighbor because the neighbor will know about it by being directly connected.

So unless there is another interface on the same router with the same subnet mask as the interface in question the router will not send any updates.

Depending on what you are trying to do RIP may not be the protocol of choice.

Let me know if you have anymore questions.

New Member

Re: RIP, supernet

Thanks for your response.

The router should advertise the subnet of another interface (loopback).

If I change the netmask to classful mask, or longer, the router starts sending RIP packets on the Ethernet interface, but when I change it back RIP stops.

Unfortunately we have to use RIP, because of the platform (SOHO 91).