OSPF Route Filtering

Hello

Fairly new to OSPF here. I have a network consisting of 6 routers running OSPF in a single “backbone” area. Each router advertises its connected prefixes as expected.

Router A — Router B — Router C — Router D — Router E — Router F

I would like to block specific routes from half the network. i.e. routes injected at Router A i would like to only propagate as far as router C. I’ve tested ospf-input route filters at router C which works for that local router however they still get sent on to router D, E and F.

Can you point me in the right direction?

Thanks

The filter of ospf-input on Router C are used when the router takes routes from OSPF to use them for the local routing table. Therefore it’s normal that D,E and F get those routes. You need to add a filter on these routers as well to avoid router os from putting them into local routing table. Can you provide a bit more details why the routes should not be propagated to C D E F?