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New Member

Invalid routes in RIP ver2

Hello all,

My company uses the Motorola Canopy system on 10 towers which are all backhauled to our core tower and then split off into C806's. Each C806 handles traffic for one tower. Each router is configure for basic routing (public to public) with rip ver2 as the routing protocol. One of the routers has a routing table that is alot bigger than the rest of them and also has invalid routes. Example- 64.198.86.0/24 is seen as 64.198.86.0/25. That router also has a problem with being over worked and chewing up bandwidth. Any suggestions would be greatly appreciated

2 REPLIES
Gold

Re: Invalid routes in RIP ver2

If this were ripv1, I would say the router with these invalid routes has an interface configured with a different mask than the other routers--a /25, specifically. RIP normally takes the prefix length from the interface through which the route is learned, since the subnet mask isn't carried in the packets.

However, this is ripv2, so this shouldn't be happeneing--unless that one router is misconfigured with ripv1, or there are some ripv1 routes making it into the network someplace or another. What I'd do is check all of the subnet masks on all the interfaces of that one router, and then check the routing information source for each of those odd routes--the next hop in the routing table. I'd then pop over to the router that seems to be advertising a disproportionate number of them, and see how it's configured, etc.

Without much more information than this, it's going to be harder to give more than a general suggestion on how to troubleshoot it. If you don't find it at first, could you post a show ip route and a show ip rip database for one or two of these routes?

:-)

Russ.W

New Member

Re: Invalid routes in RIP ver2

You were right, three of the routers running RIP ver1. Not really sure why but they were. Thanks very much for your help.

Dan B.

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