A couple of things.
- you mention iBGP but I only see two routers with different AS numbers.
- The next-hop-self doesn't serve any purpose for eBGP peers since the BGP next hop is set to self when updates are advertised to an external peer.
- Who's generating the updates and how are they generated.
- Generally AS_PATH_LOOP is caused by an AS re-advertising prefixes back to the AS it received it from. I only see one connection. Could you give us more information on your topology.
Hope this helps,
Harold Ritter
Sr Technical Leader
CCIE 4168 (R&S, SP)
harold@cisco.com
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