i would be one of those two sites, and i responded tonight. the mtu problem you found (and matt found it because he worked for this particular customer this weekend) was on the customer end of one of our links. i couldn't quite figure out what you wanted me to do about it. i'll just say for the record that it seems to be a problem between the customer's vendors' router and our router :) the customer is aware of the problem and is following up with their vendor. i was a little taken back by your note which basically sounded like:

"you've got an obvious problem, you need to fix it quick as everyone depends on this resource"

that may not be what you meant, but it sounded that way.

Oops, definitely not what I meant. I just wanted to point out to the people on this list that some people depend on MTU discovery to work right, and in the thick of everything else going on, it is easy to forget about checking. I would be interested in seeing a more complete description of the problem when you get one, because anything which causes a router to send back a packet directing me to use a 63kB MTU can't be good! I think I also jumped the gun on who I sent the report to, because the name and IP address for the router in question were in the MCI block, although I see now the router is in fact not owned by MCI. Sorry for the misleading mail. --Jamshid