full bgp routing table

beheer · ‎10-23-2007

Hi,

I'm having an issue receiving a full routing table if my primaire route goes down.

network:

ISP1-------r1-----

\

r3

/

ISP2-------r2-----

r1 and r2 are connected to the isp's via BGP

r1 and r2 are connected to r3 via ibgp

r3 receives 200k routes and 70% off these routes go to isp1

If I now disable the neighbor session to r1. R3 does not update his routing table to use the routes to isp2 and has only 50k routes.

I'm a bit reluctant posting my router configs here, please let me know which specific info is required to understand and hopefully help me resolve this issue.

gaurav_thapar79 · ‎10-23-2007

Hi,

BTW, you muct be learning 200K routes from your eBGP peer not from R3 router.

There is an ambiguity in problem statement.

But as per my understanding your problem , if correct,

please do IGP peer at R3.

Router bgp

Neighbour next-hop-self

neighbour next-hop -self

Try and share your observation, of course rate the post as well.

beheer · ‎10-23-2007

Hi,

thx for the reply.

I've got ospf set up as my igp, I thought it wasn't wise to redistribute bgp into ospf. I've got a full mesh ibgp to get all routes to r3.

I can't set up ebgp sessions between r3 and isp's. They only peer with one router.

Next hop self is already configured.

for instance, I thought r3 should have two routes to say www.google.com, and that 1 route gets into the routing table. If that route should fail the backup would automatically be set up in the routing table.

I can see the route to google at r1 and r2, but r3 has only one route that points to r1. If I disable the peering session to r1. R3 does not learn the route via r2.

gaurav_thapar79 · ‎10-24-2007

Hi,

Can you use iBGP instead of OSPF to simply the caoncept in terms of implementation and to achieve what you want?

pls revert.

beheer · ‎11-02-2007

Hi gaurav,

issue has been solved.....it was a localprefence issue.

Thx for all your comments!

gaurav_thapar79 · ‎11-02-2007

gud luck...