On Tue, Nov 10, 2009 at 3:50 AM, Matthew Petach <mpetach@netflight.com> wrote:
I've outlawed the use of multihop eBGP for load-sharing here; when we get multiple links off the same router to a peer or upstream, they are configured with multipath. We've got hundreds of BGP sessions across the network configured with multipath on them.
Do you use iBGP multipath as well to load-balance between links on different routers? I know eBGP multipath is fairly common, but I wonder how many are using iBGP multipath as well. I doubt any carriers would support it, so it's probably only useful for load-balancing outbound traffic. The problem with eBGP multipath alone is that you might want to terminate circuits from a given carrier on two different routers for redundancy reasons, but that precludes any load-balancing with eBGP multipath. Obviously your network has to be designed with equal-cost paths for iBGP multipath to be of any value. -Doug