Re: What's the point of prepend communities?

In a message written on Thu, Oct 26, 2017 at 01:54:17PM -0600, Clinton Work wrote:

I believe that Jason is asking about an ISP BGP community to prepend their AS when the BGP routes are received from the customer (not when

Yeah, I typoed my example, should have been: There are paths: 1 2 3 5 1 2 4 5 If you prepend your ASN, you get: 1 1 2 3 5 1 1 2 4 5 No difference. If you send the ISP a prepend community for 3, you get: 1 2 2 3 5 1 2 4 5 And you just forced all traffic to the second, shorter path. For only customers that are dual homed to 3 & 4 without affecting other traffic. -- Leo Bicknell - bicknell@ufp.org PGP keys at http://www.ufp.org/~bicknell/