If you have OSPF internal, and eBGP at the wan edge, how can you originate the same route at two different locations?
Usually when there’s one origin of a prefix it works fine. Packet flows via ospf until it reaches the wan edge where eBGP admin distance beats OSPF. Packet routes out to the Spoke Router, and everything’s good.
However if two sites are advertising the same prefix, then you’ll learn it eBGP from wan edge (from remote site), and also from ospf (local back end connection.)
Then no spoke Router can successfully reach the destination, because packet routes to one of the two hubs, then tries to route back out to the wan due to admin distance.
Swap distance between ospf and bgp at the wan edge Router, and then break all the actual wan spoke routes.
Either way it seems like a routing loop. Any ideas?
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