On an IX, without next-hop-self peer A leaking peer B's routes they receive to C will have C send direct to B on the IX (assuming flat layer 3 addressing, and not multiple little /30s or /96s everywhere or something - do any exchanges do that?)
This may seem more efficient than sending C's traffic to A to get to B (pumping up the IX's usage graphs) but B may not have peering agreements with C. Setting next-hop-self avoids this. An 'advantage' in some views. Not related to n-h-s in an igp specifically, but an interesting (mis)use case. /kc On Fri, Dec 01, 2017 at 03:06:34PM +0000, craig washington said: >Hello everyone, > > >Question, what are the true benefits to using the next-hop self feature, doesn't matter what vendor. > >Most information I see is just to make sure you have reach-ability for external routes via IBGP, but what if all your IBGP knows the eBGP links? > >Is there a added benefit to using next hop self in this situation? > > >Any feedback is much appreciated, either for the question specifically or whatever else you got ????, L3VPN's or underlying technology that has to have that. > > >Thanks > > -- Ken Chase - m...@sizone.org Guelph Canada
