IBGP neighbors over F/R

From: ccie2be (ccie2be@nyc.rr.com)
Date: Tue Aug 05 2003 - 13:12:42 GMT-3


Hi,

BGP wouldn't form peers between 2 spokes on a F/R hub and spoke topology.

Here are the details:

       R3---------R2----------R1
     spoke hub spoke

All routers are running OSPF and the F/R is in subnet 172.16.100.0/24 and the
f/r interfaces were all left at their default ospf network types -
non-broadcast. The neighbor command was configured on R2 to allow it to form
ospf adjacencies with R1 and R3. R1 can ping R2 but not R3 and R3 can ping R2
but not R1.

R1's loopback interface = 192.168.1.1 and R2's loopback = 192.168.2.2 and R3's
loopback = 192.168.3.3

The route table of each router shows all 3 loopbacks.

R1's BGP config:

router bgp 123
nei 192.168.2.2 remote-as 123
nei 192.168.2.2 update-source lo0
nei 192.168.3.3 remote-as 123
nei 192.168.3.3 update-source lo0

R2's config:

router bgp 123
nei 192.168.1.1 remote-as 123
nei 192.168.1.1 update-source lo0
nei 192.168.3.3 remote-as 123
nei 192.168.3.3 update-source lo0

R3's config:

router bgp 123
nei 192.168.1.1 remote-as 123
nei 192.168.1.1 update-source lo0
nei 192.168.2.2 remote-as 123
nei 192.168.2.2 update-source lo0

R1 and R3 can both peer with R2 but they don't peer with each other. I
thought that as long as there was a TCP path ( the ip addr was in the route
table), R3 and R1 could peer. But this isn't working. Can someone explain
why not?

Thanks, Raj



This archive was generated by hypermail 2.1.4 : Tue Sep 02 2003 - 18:53:53 GMT-3