Henning Brauer wrote: > i honestly don't understand your problem ;( I get told that a lot ;)
Our two border routers (I'll call them B1 & B2) both have full views made up of various transit & peering connections. They have iBGP peerings with each other and also with both of the access routers (I'll call them A1 & A2). Under normal circumstances the access routers see ~180,000 prefixes from B1 and ~12,000 prefixes from B2. If for some reason B1 loses external connectivity, there is about a 2 minute time frame where A1 & A2 only have partial connectivity as B2 loses the routes from B1 and then starts advertising more of it's own external routes. JunOS has an option that allow you to tell B1 & B2 to advertise a full table of routes to all iBGP peers so in the example of B2, it might have selected routes via B1 as active, however it will still advertise a full table of it's own best external routes. This means that should B1 lose connectivity, A1 and A2 already have a full route view from B2 and don't need to wait to it to re-converge. I'm not convinced that made much more sense. Perhaps I'm making the whole issue overly complicated? Tom
