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Forum Replies

  1. Hi Hamood,

    That’s right, if you source eBGP from the loopback interfaces then you’ll need multihop.

    The problem with the R1-R2-R3 scenario is that R2 will never learn about any prefixes, when R1 tries to reach a network behind R3 (or R3 wants to reach something behind R1) then R2 will receive an IP packet with a destination it doesn’t know about.

    If you really had to use eBGP between R1 and R3 then a GRE tunnel might be a solution…


  2. Hi Rouzbeh,

    The static routes are required otherwise there’s no way to create the BGP neighbor adjacency between the loopbacks. The routers don’t know how to reach each others loopbacks. Once the BGP neighbor adjacency, you could advertise the loopbacks but they will never be installed in the routing table since the static routes have a lower AD.


  3. Hi Rene,

    Why you enable the directly connected check again when you increase the TTL ?


  4. thanks Rene I understood that we have tow options to use, but in the first option they will not become neighbor even though “disable-connected-check” since by default the TTL for eBGP is 1 so finally we need to increase the TTL if we use the first option ? right ?

  5. I’m still not clear on why the second scenario requires multihop when the neighbours are directly connected.

    Are you saying that when traffic is sourced from and to a loopback, it is effectively taking 3 hops? (2 of which are virtual within the routers).

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