Folks, Last time I had any reasonable idea as to the time it took for network updates to propogate across the various backbones, I concluded that it took approximately 15 minutes for reachability via BGP to be advertised to what seemed like a widely dispersed set of locations. Some of them were connected either directly or indirectly to the MCI backbone, but others were connected to ANS or Sprint. Today, we had a scheduled outage of our main routing core here at Penn. We powered all of the routers back on at approximately 09:00 EDT. Until approximately 10:20 EDT, we were unable to perform nameservice lookups due to the root name servers not sending responses to us. Between approximately 09:30 EDT and 10:20 EDT, we were able to get to more and more of the root nameservers, but it wasn't untill after 10:00 EDT that any of the root namerservers were reachable. Does it really take over 30 minutes for routes to propogate across the major US backbones? [I'm ignoring the fact that we were unable to get answers to name service queries from the root name servers until after 10:20 EDT - I don't know what caused it, but for the purpose of determining how long it takes for reachability to propogate, that fact that I could ping or traceroute to the servers means that my nets were reachable.] Has anyone done any testing on this to try to determine the propogation time? Was there some major problem this morning on MCI or Sprint or some NAP? I have a net that I could use for this testing, but I need a good selection of hosts to try to ping [preferably at least one on each network providers network - ie. one for MCI backbone, one for JVNCnet/GES, one for Sprintlink, one for bob's stop-n-shop dial-up service, etc.] By the way, is there still a large amount of route flapping going on in the core routers? -------------------------------------------------- Jon Boone Operations Engineer ISC Networking University of Pennsylvania tex@isc.upenn.edu (215) 898-2477