Given the configuration and routing table in the exhibit, which routes will be advertised to OSPF neighbors because of the demo policy?
A.
192.168.0.0/16 only
B.
192.168.0.0/17 only
C.
192.168.50.0/24 and 192.168.51.0/24
D.
192.168.0.0/17, 192.168.50.0/24 and 192.168.51.0/24
This answer is not correct. OSPF has a default export policy of “Reject everything,” as LSAs are flooded by default. The default export policy blocks the advertising of additional routes from other sources, static and aggregate in this case. So, without an added term that accepts something else, nothing would be advertised as a result of this applied policy.
D is correct answer:
Route filters are lists of prefixes configured within a single routing policy or policy term. They provide a few more match types for selecting prefixes you can specify an optional action to be taken if the route-filter statement matches.
This action is executed immediately after the match occurs, and the then statement is not evaluated.
I failed to see the “accept” at the end of the route filter. As such, I am wrong and this answer is in fact correct.
Thanks your idea.
D.
192.168.0.0/17, 192.168.50.0/24 and 192.168.51.0/24
Well, I thought the answer was wrong too, but for a different reason. I noticed the 192.168.0.0/17 is an AGGREGATE route.
I understand aggregate routes are never routed ….. especially into OSPF? Which knows nothing about aggregates?
I know I must be missing something here …..
The correct answer is C