Jesper Skriver wrote:
Your Cisco router (say a GSR) will go foobar if you use 10/30 seconds timers, a IGP topology change, causing a new next-hop interface for 100k routes, will cause processes (probably CEF related) to run for so long, that you will loose your BGP keepalives, thus loose sessions, and everything will go *BOOM* - so please be nice and don't do that without real testing.
This is the exact reason why you want your liveness to be detected out of band of the actual routing protocol keepalives which might also be stuck behind a queue of incoming updates which you need to read off the socket before you can see the HELLO coming in. Of course you're toast either way if your interface queues are large enough and you don't do preferential queueing for BGP. Pete