Real World eBGP route not used question

I'm sorry to post my dirty laundry here but i have a question for my peers. This /18 is recieved from multiple directly connected eBGP peers but it is not entered into the routing table although it is passed to iBGP peers. what is in the routing table is a longer parent route from an iBGP peer. Because of this i have a routing loop between iBGP peers for an external route.

I don't understand. The route is Valid, best but there is no * associated with it so it never goes to the route table. The eBGP peers are directly connected (without multihop) so next hop cannot be an issue.

I'm using OER but this /18 is not in the OER path list.


R-LANaut#sh ip bgp bestpath
BGP routing table entry for, version 508560
Paths: (2 available, best #2, table default)
  Advertised to update-groups:
     2          8        
  6939 7270 from (
      Origin IGP, localpref 100, valid, external, best
R-LANaut#sh ip route
Routing entry for, supernet
  Known via "bgp xxxxx", distance 200, metric 100
  Tag 174, type internal
  Last update from A.B.C.D 20:35:42 ago
  Routing Descriptor Blocks:
  * A.B.C.D, from A.B.C.D, 20:35:42 ago
      Route metric is 100, traffic share count is 1
      AS Hops 3
      Route tag 174
      MPLS label: none


  • Do you have a route to

  • What does the command "show ip bgp rib-failure" tell you?


  • this is a directly connected eBGP peer. It is on a GIGE port.

    R-LANaut#sh ip route
    Routing entry for 216.66.x.x/x
      Known via "connected", distance 0, metric 0 (connected, via interface)

  • This /18 is not in RIB failure or it would say so in the "sh ip bgp x.x.x.x" output.

    But to answer your question dierctly, neither the /18 subnet nor the next-hop are listed in the "sh ip bgp rib-failure" output.



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