BGP to OSPF - NSSA default information originate - conditional

[Bilal Nawaz]

Hello,

I have an ASBR and another router within the same NSSA area. The ASBR has a BGP peering with ISP and is receiving prefixes 0.0.0.0/0 and 1.0.0.0/24.

1.0.0.0/24 is not in the ISP AS, but learned route from another AS.

I know that when I issue the command 'area 254 nssa default-information-originate', a default route is generated in to the nssa area which is fine. However, I want to have the option to do this command 'default-information originate route-map AS1_DEFAULT_IF1'

This would say inject the default route downstream only if 1.0.0.0 is in the routing table. But when command is issued, this doesn't work. Could anyone tell me why this doesn't work?

I'm trying to follow this document, on section 6-14 at the bottom https://learningnetwork.cisco.com/servlet/JiveServlet/previewBody/3423-102-1-9434/ccmigration_09186a008014ee4e.pdf

In this case it is suggested the NSSA area is used, what harm is there if I use a normal area (not area 0). Because the non NSSA solution will work fine.

ASBR:

router ospf 254

log-adjacency-changes

area 254 nssa

default-information originate always route-map AS1_DEFAULT_IF1

!

ip prefix-list bgplist seq 5 permit 1.0.0.0/24

!

route-map AS1_DEFAULT_IF1 permit 10

match ip address prefix-list bgplist

show ip route

B*   0.0.0.0/0 [20/0] via 172.16.10.1, 10:00:07

B       1.0.0.0 [20/0] via 172.16.10.1, 09:56:20

O       172.16.252.0 [110/20] via 172.16.254.2, 00:21:48, FastEthernet0/0

C       172.16.254.0 is directly connected, FastEthernet0/0

C       172.16.10.0 is directly connected, FastEthernet0/1

[blau grana]

Hello Jose,

Sorry, my mistake. I thought that Bilal used nssa area only because example in pdf used it.

In this case it is suggested the NSSA area is used, what harm is there  if I use a normal area (not area 0). Because the non NSSA solution will  work fine.

Now we can leave this thread rest in peace

Best Regards

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