On 5/11/2010 11:35, Jay Nakamura wrote: > So, we have two upstreams, both coming in on Ethernet. One of our > switch crashed and rebooted itself. Although we have other paths to > egress out the network, because the router's Ethernet interface didn't > go down, our router's BGP didn't realize the neighbor was down until > default BGP timeout was reached. Our upstream connectivity was out > for couple minutes. > > I am looking for ways to detect neighbor being down faster so traffic > can be re-routed faster. I can do BFD internally but the issue is how > the upstream is going to detect the outage and stop routing our > traffic to that downed link. I have asked both of my upstreams and > one said they don't do anything like that, second upstream I am still > waiting on the answer. > > My question is, do other carriers do BFD or any other means to detect > the neighbor being down faster than normal BGP will allow? (Both > upstreams are major telcos [AT&T and Qwest], so I think they are less > flexible than some others.) > > Or, has anyone succeeded in getting something done with those two carriers? >
In my experience this is a pretty common problem with carrier Ethernet links where the interface is always "up" unless the directly connected switch/mux fails. Even then, it may still keep the port up through reboots. I like how Ethernet is cheap, but I hate how it lacks simple things like "link is down if any segment of the L1 or L2 between endpoints faults" that you get without silly tricks on a DSx or OC-x. (Then again, I suppose you're paying for that capability if it's important enough.) ~Seth
