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Can OSPF do this


Can anybody help me... in this..

I am trying to find solution through OSPF for the following requirement.

I want loopback Interface1 of routerA to be advertised through framerelay link to RouterB and not to advertise loopback interface2 on the routerA through framerelay link to RouterB but it should be advertised only through Dial up link from routerA to RouterB.

My idea is that in this way I can monitor network properly

My colleague told he can do this through EIGRP by dialer watch but I want to use OSPF.

Any suggestions are welcome

Thank you

Sunil Kumar


Re: Can OSPF do this

I understand your requirements to be that loopback2 should only be advertised out the ISDN link and only when the frame dies.

You can filter LSA's from being sent via the ip ospf database-filter all out command, but that is more than you want. You can have a distribute-list in on routerb but that won't prevent it from receiving the LSA's, it just will prevent the route from entering the routing table. Again, not what you want.

I think you best choice is to create loopback2 under a different routing process (eg rip or eigrp and passive interface it on all other interfaces) and redistribute that route into ospf. Then on serial interface (frame link) use distribute-list out and filter that route. The command distribute-list out works only on the routes being redistributed by the autonomous system boundary routers (ASBRs) into OSPF. It can be applied to external type 2 and external type 1 routes, but not to intra-area and inter-area routes.

Hope it helps.


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