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New Member

BGP negibhors. Same remote AS


using private AS numbers. RouterA is set for AS 1. I already have a neighbor to RouterB configured for remote AS 2 through a wan connection. I want to peer with RouterC through an ethernet connection but they are also using AS 2. Is this possible? The AS numbers used in this post are just an example

Thank you,


Re: BGP negibhors. Same remote AS

Yes, it is possible. As long as the IP reachability is there between the peering devices it should work fine. BGP peering doesn't care about the underlying media type used and in other words, it's media independent. You can have a single router with multiple peers in another AS.




Re: BGP negibhors. Same remote AS

It is possible but be aware that you now running what is referred to as internal BGP (iBGP):

Re: BGP negibhors. Same remote AS


The conenction between router A and router C would still be an EBGP connection as they are in different AS.

IF you plan to run BGP between router B & C then it would be an IBGP conenction.



Re: BGP negibhors. Same remote AS

RouterA = AS1

RouterB = AS2

RouterC = AS2

RouterB and RouterC should be in iBGP

It's definitely possible to connect RouterA to both RouterB and RouterC using eBGP. With this, RouterA will have distributed/redundant connection to AS2

If there is no interconnection between RouterB and RouterC, let us know.

New Member

Re: BGP negibhors. Same remote AS

RouterB and routerC are different customers. They happen to be using the same AS numbers that can't be modified. RouterA needs to peer with each of them. Filtering would be needed to prevent routing between these two entities.

I would like to thank everyone that has posted a response to my original question


Re: BGP negibhors. Same remote AS

You already wrote a thank you note, thus that mean everything is okay now?

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