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Cisco BGP Keeps on Bouncing

Hello Experts,

Can someone please take a look at configs and please tell me why BGP keeps on bouncing between HongKong and London_Nr1?

I have configured ebgp-multihop 2 on both but it still keeps on bouncing.... see below

Below is output from Hongkong
Aug 31 19:39:22: %BGP-3-NOTIFICATION: received from neighbor 4/0 (hold time expired) 0 bytes
Aug 31 19:39:22: %BGP-5-ADJCHANGE: neighbor Down BGP Notification received
Aug 31 19:40:07: %BGP-5-ADJCHANGE: neighbor Up  
Aug 31 19:46:25: %BGP-5-ADJCHANGE: neighbor Down BGP Notification sent
Aug 31 19:46:25: %BGP-3-NOTIFICATION: sent to neighbor 4/0 (hold time expired) 0 bytes  
Aug 31 19:47:17: %BGP-5-ADJCHANGE: neighbor Up

And the below is the output from London_Nr1.

Aug 31 19:23:20.347 GMT: %BGP-5-ADJCHANGE: neighbor Down BGP Notification sent
Aug 31 19:23:20.347 GMT: %BGP-3-NOTIFICATION: sent to neighbor 4/0 (hold time expired) 0 bytes
Aug 31 19:24:20.396 GMT: %BGP-5-ADJCHANGE: neighbor Up

Do you think its because of the route-reflector?

Do I need to set up a connection between hongkong and the route-reflector?

Please be mindful that the ASN's are completely different , hence why I'm having to use eBGP

Your expeditious help will be greatly appreciated..


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1 Solution
I don't think its to do with the route reflector - the purpose of the RR is for IBGP, not EBGP.

I noticed hongkong does not have bgp update source configured.  That maybe part of the problem.

You are using multihop, meaning you will need a route between the loopbacks before BGP will establish.  You seem to be using OSPF to establish that route.

This is where I think you are going to run into problems - OSPF and BGP are going to be clashing over who is the best routing and I think this is causing your instability.  

Two routing protocols for the same interfaces and routes is generally a bad practice.
cpatte7372Author Commented:
Unfragmented, thanks for responding. In the past I have configured hong kong with update source, but BGP still kept on bouncing.

Anyway, do you have any ideas on how to get over the problem with OSPF and BGP clashing if that's the problem?

keep ospf as the IGP of AS44356.  But do not run it on the link to hongkong.
eBGP will break as a result, but don't worry - fix that up with a static host route on each eBGP router.  That should stabilize BGP.  Then ensure prefixes are advertised correctly, either with explicit annoucements or redistribute OSPF into BGP.
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cpatte7372Author Commented:
Hi unfragmented, thanks again. I will try your suggestion in a couple of hours. I will let you know how I get on.

cpatte7372Author Commented:

It worked like a dream.

Cheers mate...
cpatte7372Author Commented:

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