Karl, > Specifically, we are working on a lab with three routers running BGP. They > are in the same AS (IBGP). They are not fully meshed one is acting as a > router reflector for the other two. One of the RR clients has a loopback > injected into BGP by redistribute connected. All three routers are also > running OSPF and have an IGP route to the same network being injected into > BGP. The route is synchronized on the router it is injected into and on the > route reflector, but it isn't synchronized on the other route reflector > client. We are aware of how BGP and OSPF router IDs can prevent > synchronization, so we have specified the same router IDs for BGP and OSPF. >
What version of IOS? You can try to verify the ospf next-hop and bgp learned next-hop, if they are different and the ospf has a higher admin distance than your bgp, bgp will show a RIB failure. CSCdx26714 for more information. HTH Kent ""Karl Brusen"" wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > Can anyone point me towards a resource that describes in detail what it > takes for BGP to consider a route synchronized when it learned it through > IGP OSPF? My study partner and I are struggling understanding how it works. > All of our resources provide only general information with statements like, > "a route must be learned by IGP before BGP will consider it synchronized". > Merely learning a route from IGP is apparently not good enough. There must > be other, more specific requirements. How does route-reflection affect > BGP/OSPF synchronization? > > Specifically, we are working on a lab with three routers running BGP. They > are in the same AS (IBGP). They are not fully meshed one is acting as a > router reflector for the other two. One of the RR clients has a loopback > injected into BGP by redistribute connected. All three routers are also > running OSPF and have an IGP route to the same network being injected into > BGP. The route is synchronized on the router it is injected into and on the > route reflector, but it isn't synchronized on the other route reflector > client. We are aware of how BGP and OSPF router IDs can prevent > synchronization, so we have specified the same router IDs for BGP and OSPF. > > What is interesting is that if we point a static route from the problem > route-reflector client to the BGP route "next hop", BGP synchs. Due to the > network topology and modifications of the ad distance, the problem router > also has a route learned from EIGRP but is not normally in the IP routing > table. When we shut down an interface so that the EIGRP route is placed in > the IP routing table, BGP synchs. > > We are very confused. There is something about how BGP synchs with OSPF > that we just don't understand. Any insight from the group will be greatly > appreciated. > > Thanks, > > > Karl Brusen Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=53062&t=52980 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
