Can't ping a loopback address learned through IBG

NewInBussinesNewInBussines Member Posts: 28 ■□□□□□□□□□

Please help me with the following problem:

I have a setup in GNS3 with 5 routers, on four of them I am running IBGP and on 2 I am running EBGP.I set up the neighbor relationship using peer-group in IBGP, I have set manually the neighbors for EBGP.
I will put a picture and explain what I did;))


  • srgsrg Member Posts: 140
    Please share a picture and some relevant config, your post doesn't really explain anything :P
  • Mrock4Mrock4 Banned Posts: 2,360
    Do a "show ip bgp" and ensure the route is listed as "*>" on the left (meaning it is currently being installed into the routing table). If it does show this, do a "Show ip route x.x.x.x" where x = your loopback interfaces IP address. See where the router is sending traffic destined to that loopback. Run a traceroute to that loopback..access the devices along the path and verify they are routing properly (and have routes installed to that loopback). Once you get to the router running the loopback, do the same, but in reverse, ensuring the source for the loopbacks are found in the routing table of each device.
  • networker050184networker050184 Mod Posts: 11,962 Mod
    The reason for this about 90% of the time is the source of your ping. Ensure the adress of the outgoing interface is reachable from the other end.
    An expert is a man who has made all the mistakes which can be made.
  • powmiapowmia Users Awaiting Email Confirmation Posts: 322
    add "next-hop-self" to your peer-group neighbor, or add the external peering links to your IGP.
  • deth1kdeth1k Member Posts: 312
    as already mentioned, source your pings from loopback assuming you've injected it into iBGP. If those loopbacks are originated by your eBGP peers, iBGP routers peering eBGP need to have next-hop-self applied to the peer-group.
  • networker050184networker050184 Mod Posts: 11,962 Mod
    I sure hope he's figured it out after a month!
    An expert is a man who has made all the mistakes which can be made.
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