On May 28, 10:37am, "Sam Stickland" <sam_ml@spacething.org> wrote:
Are there any BGP extensions that would cause a BGP speaker to foward all of it's paths, not just it best? I believe quagga had made some recent attempts
It has been discussed and been on wish lists, but:
in this direction. IIRC the problem isn't to do with the route annoucements, it's the route withdrawals. I believe BGP only specifies the prefix being withdrawn and not the path, so if it's advertised multiple paths to a prefix it's impossible to know which has been withdrawn.
That is 100% correct, yes. Selective withdrawal is not supported. Another issue is that there isn't much point, as far as regular BGP and routing considerations go. Whichever is the best path for a border router is the best path; telling other routers about paths it will not use serves no (or at best very little) point in this context. Funny coincidence, just earlier today I was talking to somebody about BGP and its general applicability, and while there can be no question that BGP has stood the test of time and achieved all its objectives, there are things one would do differently if one were to start over. But that's always the case. Best, -- Per