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Having a strange issue can't seem to figure out what's happening. I got 2 routers running BGP. Router A is advertising 23.128.128.0/24 subnet and Router B is advertising 23.128.129.0/24. Routing is working fine from the internet and I can access both subnets from any location in the world. Both routers share the same AS number though. The problem I am facing is that when I try to see BGP route for any of the subnets from router B, I can't seem to find any route.

SSH@YLINX-CORE-2024C-4X-TX#sh ip bgp routes 23.128.129.0/24 BGP4 : None of the BGP4 routes match the display condition

While strange enough If I try to see subnets for router A on router B it should be the BGP route.

SSH@YLINX-CORE-2024C-4X-NY#sh ip bgp route 23.128.128.0 Number of BGP Routes matching display condition : 1 Status A:AGGREGATE B:BEST b:NOT-INSTALLED-BEST C:CONFED_EBGP D:DAMPED E:EBGP H:HISTORY I:IBGP L:LOCAL M:MULTIPATH m:NOT-INSTALLED-MULTIPATH S:SUPPRESSED F:FILTERED s:STALE x:BEST-EXTERNAL Prefix Next Hop MED LocPrf Weight Status 1 0.0.0.0/0 209.137.137.189 0 100 0 BEx AS_PATH: 4459 Last update to IP routing table: 1h0m25s, 1 path(s) installed: Route is not advertised to any peers

Can't seem to figure out what is the problem. Any pointers would be helpful.

Thanks.

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    By default most router will not accept a route received with is own AS number as originator from an eBGP peer. Check if you can add a command to tell the router to accept his local-AS. – JFL Sep 1 '18 at 8:16
  • Awesome .. that did the trick :) Completely missed that earlier. Thanks for the quick response. – NBhatti Sep 1 '18 at 8:54
  • Glad it works. I have put my comment as an answer so you can except it and the question don't pop-up forever looking for an answer. – JFL Sep 1 '18 at 11:49
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Most routers by default don't accept a route from an eBGP peer where the originator is their own AS number.

You need to configure the router to accept it's local AS, then the route will be installed in the forwarding table.

I don't know the specific command for a brocade router, it is usually something along allowas-in.

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