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  1. Hi Rene!
    In "R3#show ip bgp 1.1.1.1" we see this output:
    192.168.12.1 (inaccessible) from 192.168.23.2 (192.168.23.2)
    My BGP Quagga-based router with same configuration doesn't make recursive lookup in BGP table and just doesn't insert the route for 1.1.1.1 in routing table. Though it is in "show ip bgp ..." outputs.
    Next-hop-self or route-map's "set" options don't work with RR.
    How could i make this to work?

  2. Rene,

    If this has been answered by other members I apologize but following your example, the RR works as configured as R3 does learn about the 1.1.1.1/32 prefix but its not being installed in the routing table because it can not reach the next hop address of 192.168.12.1. To resolve this I added the next-hop-self command on R1 and reset the BGP peerings. That still did not resolve this.

    My question is once a RR is configured should all the clients update their next hop to the RR or should the originator of the prefix have the next-hop-self configuration?

    R3#sh ip bgp 1.1.1.1
    BGP routing table entry for 1.1.1.1/32, version 0
    Paths: (1 available, no best path)
      Not advertised to any peer
      Refresh Epoch 2
      Local
        192.168.12.1 (inaccessible) from 192.168.23.2 (192.168.23.2)
          Origin IGP, metric 0, localpref 100, valid, internal
          Originator: 1.1.1.1, Cluster list: 192.168.23.2
          rx pathid: 0, tx pathid: 0

    -

    R1#sh running-config | section router bgp
    router bgp 123
     bgp log-neighbor-changes
     network 1.1.1.1 mask 255.255.255.255
     neighbor 192.168.12.2 remote-as 123
     neighbor 192.168.12.2 next-hop-self
  3. HI Michael,

    Good to hear you got it working :slight_smile: I hope that I can start working on the multicast lessons in a few weeks...to be continued :wink:

    Rene

  4. Using the "neighbor x.x.x.x next-hop-self all" command on RR will solve the iBGP next-hop problems when using RRs.

    Below is the config i Labed and it just worked:

    Leaf1#sh run | sec bgp
    router bgp 1234
     bgp log-neighbor-changes
     network 10.1.1.0 mask 255.255.255.0
     neighbor 11.11.11.2 remote-as 1234
     neighbor 21.21.21.2 remote-as 1234
     maximum-paths ibgp 64

    Leaf2#sh run | sec bgp
    router bgp 1234
     bgp log-neighbor-changes
     neighbor 12.12.12.2 remote-as 1234
     neighbor 22.22.22.2 remote-as 1234
     maximum-paths ibgp 64

    Leaf3#sh run | sec bgp
    router bgp 1234
     bgp log-neighbor-changes
     network 10.2.2.0 mask 255.255.255.0
     neighbor 13.13.13.2 remote-as 1234
     neighbor 23.23.23.2 remote-as 1234
     maximum-paths ibgp 64 #ECMP

    Spine1#sh run | sec bgp
    router bgp 1234
     bgp log-neighbor-changes
     neighbor S1_L1_L2_L3 peer-group
     neighbor S1_L1_L2_L3 remote-as 1234
     neighbor S1_L1_L2_L3 route-reflector-client
     neighbor S1_L1_L2_L3 next-hop-self all
     neighbor 11.11.11.1 peer-group S1_L1_L2_L3
     neighbor 12.12.12.1 peer-group S1_L1_L2_L3
     neighbor 13.13.13.1 peer-group S1_L1_L2_L3

    Spine2#sh run | sec bgp
    router bgp 1234
     bgp log-neighbor-changes
     neighbor S2_L1_L2_L3 peer-group
     neighbor S2_L1_L2_L3 remote-as 1234
     neighbor S2_L1_L2_L3 route-reflector-client
     neighbor S2_L1_L2_L3 next-hop-self all
     neighbor 21.21.21.1 peer-group S2_L1_L2_L3
     neighbor 22.22.22.1 peer-group S2_L1_L2_L3
     neighbor 23.23.23.1 peer-group S2_L1_L2_L3

    Leaf1 : BGP and route table:

         Network          Next Hop            Metric LocPrf Weight Path
     *>  10.1.1.0/24      0.0.0.0                  0         32768 i
     *mi 10.2.2.0/24      21.21.21.2               0    100      0 i
     *>i                  11.11.11.2               0    100      0 i
    
          10.0.0.0/8 is variably subnetted, 3 subnets, 2 masks
    B        10.2.2.0/24 [200/0] via 21.21.21.2, 00:31:39
                         [200/0] via 11.11.11.2, 00:31:39
  5. andrew says:

    Udaya,
    In the case of a router's being a route reflector client of multiple route reflectors, the client will accept routes from all reflectors. In other words, all learned routes will be present in the BGP topology table. As far as which routes are selected as best routes, and installed in the routing table, the client will use the standard (and complex!) BGP best path selection algorithm.

Continue the discussion forum.networklessons.com

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