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(Routing-101) Protocol redistribution question BGP into OSPF
Working on what I thought was going to be an easy solution - but hey... Have 2 campus networks with 2 different autonomies now joined together. As an initial step we will leave the different autonomies and try to glue them together. Each campus has a distinct OSPF network and each campus has separate BGP peering sessions with unique AS's at it's borders. What we are trying to do is this. The campuses are connected via 2 PtP circuits that are internal to each campus. We have established separate BGP peering on each circuit - completely distinct from one another. We chose iBGP because of some 3rd party sites that are dual homed to each campus, local-pref seemed to be the best way to deal with route preference. So each site is using the same ASN on these internal iBGP sessions. But there are 2 main peering routers and at each campus (i-e: not a full mesh but 2 separate iBGP instances). The routers on the same campus do not peer with one another. Rather each router in addition to the BGP session is an ASBR into a common OSPF area on each campus. The thought is that the routes learned from iBGP will be redistributed and weighted via OSPF into the local campus WAN. There are 3 entry points into each LAN from a BGP/OSPF transition - each is independent of the other and each will originate default into OSPF. Now the quandary is this - how to get the campus routes to exchange from BGP - to OSPF and back again - *without enabling* "redistribute internal" on BGP. A few of us are/were of the opinion that once the routes are populated in the routing table from BGP - the OSPF instance would then re-advertise them since they are valid routes (of course with a specific network statement in OSPF) but practice is telling us that this is not working. The only way we can get this working at all is by enabling "redistribute internal" in BGP and then redistributing BGP in OSPF with a route filter. Does anyone have something similar working with a method differing from "redistribute internal" in BGP. Please contact me off-list. -- Rich Sena - email@example.com ThickNET Consulting "On the way to understanding; you understand, and forget."