Configuring Specified interfaces in ospf

WhyMe_08

Hi
if you were to configure two interfaces between two routers and the questions says "place the connection between router A and router c in ospf area 0" , would you have to use the 0.0.0.0 wildcard mask for those specific interfaces?? or you can use the 0.0.0.3 wildcard matching the network mask specified for the interfaces??

Forsaken_GA

Either, or. Basically, the only thing the network statement does is see which interfaces have IP's that match that mask, and then enable them in OSPF.

so if fa0/0 has IP 192.168.1.1 and you do

network 192.168.1.1 0.0.0.0 area 0
it's the same as if you did 192.168.1.0 0.0.0.255 area 0

I personally prefer to be as specific as possible in my network statements so that I don't accidentally enable interfaces I didn't mean to.

For example, let's say fa0/0 has 192.168.1.1/25 and fa0/1 has 192.168.1.129/25 configured

then network 192.168.1.0 0.0.0.255 area 0 would match both interfaces, and that might not be something that I want.

These days, I enable OSPF at the interface level with the ip ospf <proc id> area <area id> command instead. This way I know for sure I'm only getting the interfaces I want in OSPF, and since that's how you have to do it to enable ospfv3 anyway, I figured I might as well get used to it.

kmcintosh78

Learn something new every day.
I do like the idea of drilling down as much as possible.

Thanks for that.

WhyMe_08

thanks very much for that explanation it really went deep. i like that. hope i could get these kind of explainations
from my class instructor. thanks a million.