The topology we are discussing: M / \ A B * Peer link | * | Customer link RRRRRRR Point1 * * Point2 VVVVVVV Vince Fuller said:
What we are seeing, though, is "R A M" at Point1 and nothing at Point2, likely because Randy doesn't consider "R B M", received from one of his peers, to be a customer route.
I suppose that R should change their policy, so that all routes to M get treated as customer routes, even if non-customers appear in the path between R and M. Then R would announce "R A M" to V at Point1, and would announce "R B M" to V at Point2, and V would be happy. But if A and B have other providers (P, Q), or if B peers with V, then V is likely to see some non-zero number of paths like "P A M", "P B M", "Q A M", "Q B M" or "B M" at or near Point2, and so V will not actually have to carry M's traffic all the way from Point2 to Point1. In this case, V should be happy despite R's failure to announce "R B M" at Point2. David Schwartz said:
It is not consistent policy to route to a customer through both another customer and a non-customer. That's what you can't do.
M might very well have requested R to consider the paths "R A M" and "R B M" to be equally good, and M doesn't care that A is a customer of R but B is not a customer of R. It's perfectly reasonable for R to accede to M's wishes in this regard.
Alternatively, if you do decide you must accept routes to a customer from a non-customer, you must consider those routes to be customer routes.
Agree. --apb (Alan Barrett)