3

Imagine this scenario:

R1-------R2

R1's serial 1 is connected to R2's serial 1, it's a simple p2p link. Quite simple, right?

When I changed the network type on the both sides to non-broadcast, for any unreasonable reason, the adjacency dropped and everything collapsed :) I know about OSPF network types and am also well aware of the troubleshooting process. I issued almost any show/debug command; everything mostly matches on both sides: timers, area, etc. But it doesn't work, why? How do I get it working?

5

When you change the type to non-broadcast, you prevent the routers from multicasting their hellos (and everything else). Since they can't send hellos to each other, the adjacency drops.

As a troubleshooting hint, you should have seen that in the debugs -- OSPF was not sending hellos out that interface.

You can fix this by explicitly defining the neighbors using the neighbor statement under ospf

router ospf 1
neighbor 1.1.1.1

Hellos and LSAs will be unicast to the defined neighbor.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.