Using route maps to deny certain advertisements in OSPF

[lucas.shelton1]

We are using a Palo Alto as an ABR, an interface (internet facing) in area 1, another interface (LAN facing) in area 0.  In area 1, we are advertising a /19 to our various internet edge devices (redundant DC's/internet connections).  My LAN devices are seeing this /19, and I don't want them to have all this information in their routing table.  They are also getting a default route from our edge device.

My question is, how do I configure the route-map on the LAN devices (two 5596's) to reject this /19?

[Carlos Villagran]

Hi!

Please configure in the SW/RT you do not want to be receiving the routes:

ip prefix-list [word] permit 0.0.0.0/0 ge 19 le 19   <<< this would drop EVERY route /19 in the route table so change the 0s for the actual subnet you do not want to receive

route-map [word] deny 5

match ip address prefix-list [word]

route-map [word] permit 10

router ospf x

distribute-list route-map [word] in

Hope it helps, best regards!

JC