Preventing Cisco PIX/ASA5520 from advertising ospf default route to zone

Question

I have an ASA5520, and I want to run ospf on it. It has 4 interfaces. I only want the default-information originate to advertise on one interface. How would I do that?

Answer 1

It would be extremely dirty, but you can try to block protocol 89 IP packets for those 3 interfaces (inbound and outbound).

Just guessing, if want to steer traffic, consider declaring some routes as static, or imposing heavy weights on un-preferred links (whatever that machine SW allows).

Answer 2

Hi.

Do you want OSPF to advertise other routes than the default route on the 3 other interfaces?

If you're just interested in advertising OSPF on the one interface, just add that interface's IP under the OSPF area configuration (for instance, 10.0.0.1 255.255.255.255), and it will be the only interface doing advertising.

If you want all interfaces to advertise OSPF routes, you have to make two areas. One without default information originate for the first 3 interfaces, and one other area for the interface that should advertise default information.

Answer 3

Make the particular interface you want to advertise the default route on a stub.