Re: OSPF - BGP reachability

From: Kirk Graham (kgraham@instructors.net)
Date: Sun Jul 17 2005 - 22:26:22 GMT-3


Looks to me like you're missing some things. I can't see how the 192. route
shows up on the Internal router. The Provider is not advertising that
route. You either need a "redistribute connected" or a "network" statement
on Provider. Maybe you have that but didn't show it.

If it is indeed showing up in the bgp table on internal, but not working,
then the most likely culprit is that you're missing "no synch" on Internal.
Maybe you have that, but its not showing up in the configs you sent.

It looks like you're advertising your loopback from Edge to Internal with OSPF.

There are other things, but that doesn't seem to involve your problems.

Hope this helps,
Kirk

At 03:27 PM 7/17/2005, Schulz, Dave wrote:
>Group -
>
>Here is a probably that I experienced in the lab this afternoon.......
>I have 3 routers set up .... 2 are in ibgp 123(Internal & Edge)....and
>one in bgp 456 (Provider).......
>
>Setup is like this...... Internal(BGP123) - - - - Edge(BGP123 - - - -
>- Provider (BGP456)
>
>Configs are : (non-pertinent information omitted)
>
>PROVIDER:
>interface Loopback0
> ip address 192.20.11.1 255.255.255.0
>!
>interface Serial0/0.1 point-to-point
> description Provider to Edge
> ip address 150.1.0.2 255.255.255.252
> frame-relay interface-dlci 100
>!
>router bgp 456
> no synchronization
> bgp log-neighbor-changes
> network 128.20.12.0 mask 255.255.252.0
> neighbor 150.1.0.1 remote-as 123
> no auto-summary
>!
>
>EDGE:
>interface Loopback0
> ip address 172.16.0.1 255.255.255.255
>!
>interface Serial0/0.1 point-to-point
> description Edge to Internal-Core
> ip address 172.16.1.6 255.255.255.252
> frame-relay interface-dlci 101
>!
>interface Serial0/0.2 point-to-point
> description Edge to Provider
> ip address 150.1.0.1 255.255.255.252
> frame-relay interface-dlci 100
>!
>router ospf 123
> log-adjacency-changes
> network 172.16.0.0 0.0.255.255 area 0
> default-information originate
>!
>router bgp 123
> bgp log-neighbor-changes
> network 197.1.0.0 mask 255.255.0.0
> aggregate-address 197.1.0.0 255.255.0.0 summary-only
> neighbor PG peer-group
> neighbor PG remote-as 123
> neighbor PG update-source Loopback0
> neighbor PG route-reflector-client
> neighbor PG next-hop-self
> neighbor 150.1.0.2 remote-as 456
> neighbor 172.16.0.3 peer-group PG
> neighbor 172.16.0.2 peer-group PG
>
>
>INTERNAL:
>interface Loopback0
> ip address 172.16.0.2 255.255.255.255
>!
>interface Serial0/0.2 point-to-point
> description Internal-Core to Edge
> ip address 172.16.1.5 255.255.255.252
> frame-relay interface-dlci 101
>!
>interface FastEthernet0/1
> no ip address
> shutdown
> speed auto
> half-duplex
>!
>router ospf 123
> log-adjacency-changes
> passive-interface Loopback0
> network 172.16.0.0 0.0.255.255 area 0
>!
>router bgp 123
> bgp log-neighbor-changes
> neighbor 172.16.0.1 remote-as 123
> neighbor 172.16.0.1 update-source Loopback0
> no auto-summary
>!
>
>
>The bgp database appears correct on all routers. And, I can ping the
>loopback interface on the "provider router" (192.20.11.1) from the Edge
>router, but for some reason....i cannot ping it from the Internal
>router. I have racked my brains trying every which way to get to it.
>Yet, I can see it in the bgp table of the internal router with the next
>hop as being the edge router. The ibgp and ebgp appears to be in order,
>but something is definitely missing. Any ideas?
>
>
>Dave Schulz
>Email: dschulz@dpsciences.com <mailto:dschulz@dpsciences.com >
>
>_______________________________________________________________________
>Subscription information may be found at:
>http://www.groupstudy.com/list/CCIELab.html



This archive was generated by hypermail 2.1.4 : Sun Sep 04 2005 - 17:00:30 GMT-3