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iBGP - physical connection needed between peers?

Hi, I'm hoping someone can help with this. I have two edge routers (A, B) running eBGP to two separate peers (1, 2) within my colo facility. I have a single Catalyst 4500 w/ dual Sup II's, acting as my core switch, which is connected to routers A, B. I am running EIGRP in my LAN, and I am redistributing the default gateways into EIGRP. My question is in order to run iBGP between my edge routers, do I need a direct physical connection between them, or can my colo provider somehow do multi-hop iBGP for me between them?

Reply to
response3
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iBGP doesn't require a direct connection between peers, it supports multi-hop automatically. This is because the default configuration of iBGP is a full mesh of all the routers in the AS, but there's no expectation that there will be a physical full mesh.

Reply to
Barry Margolin

Thanks for the reply. I've heard about issues with syncronization problems between iBGP and eBGP, which suggest there may be issues using multi-hop iBGP. Are you aware of any such problems?

Reply to
response3

ibgp does not change the next hop address (to get it to, you will need to use the neighbor x.x.x.x next-hop-self command) ibgp will not advertise ibgp learnt routes to ibgp neighbours (unless you do something fancy like route-reflect).

i think what you are getting at is the issue of turning sync off and having a non-bgp speaker in the path -- that router will need to know (via IGP) how to get to the ibgp-learnt prefixes.

SysAdm

Reply to
itstime

Got it. Thanks for the help!

Reply to
response3

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