Confederation Question

[Dean Romanelli]

Hi All,

If I am implementing BGP confederations within an iBGP AS, does every router in that iBGP AS need to belong to a Confederation/sub-AS?  Or can I have routers that are only in the overall iBGP AS?  If I can, when I peer them to a peer that belong to a Confederation, do I specify neighbor x.x.x.x remote-as <overall iBGP AS> or neighbor x.x.x.x remote-as <sub-AS>?

[cadet alain · Accepted solution]

Hi,

You can't do this, specifying neighbor AS as subconfed AS will result in peering not completing and configuring neighbor as confederation AS will make the peering complete but as soon as you advertise a prefix in the subconfed and it is sent to the peer in the confed it will result in BGP notification and peering going down.

https://learningnetwork.cisco.com/thread/54877

Regards

Alain

[Dean Romanelli]

Sounds good.  I thought that would be the case.

Thanks Alain.