The assymmetric path is similar enough for both IP spaces to discount this possibility: no duplicate ACKs or packets are ever seen, removing the possibility of ANY end-to-end loss. The fact that its 100% reproducable and always gets stuck on the same packet furthers another suspicion: Someone told me that broken reverse DNS may do such things on certain servers: they start to throw out content, then suddenly block on the reverse DNS lookup and stop the flow right in the middle. I haven't been able to produce the problem with any other site so far though. The site in question does have a DNS problem, which leads me to the next set of questions: Is a delegating nameserver (namely UUnet's) supposed to dish out glue A RR records for the servers it delegates to ? (in the "additional records" section of the answer) If yes, does it do so only if root-nameservers have an A RR for such a server (e.g. a registered nameserver) ? Are delegations to servers that are NOT registered breaking RFCs and thus 'illegal' ? Will Networksolutions ever update name server registrations, again ? Renaming doesn't work for me: the form processor complains about the new server name not being registered. That's not the idea in a "rename" operation, really. Thanks, bye,Kai At Wednesday 08:29 PM 3/15/00 , Yu Ning wrote:
Hi,
It's very interesting that i encountered this problem yesterday. If i'm not mistaken: you have different source address block which have different trace delay to the same external site? The huge jump of delay is up to the source address, not the host OS. Right ?
So i think it may be the reason of asymmetric routing. In more detail, say we you have source addr. A, B, and external destination C. Your trace A->C has a larger delay than B->C . The reason is that the backward path from C->A is different than C->B (it's very possible, because you, or your upstream may advertise add block A, B differently), which has a larger delay.
You can verify this in this way. Let's A, B trace to a same external traceroute server address (say net.yahoo.com, or others). You may find they have the same OUTBOUND path. But then trace back from the traceroute server to A, and B, i believe you will find the difference.
hope this help, regards.
Yu Ning
-------------------------------------- (Mr.) Yu Ning ChinaNet Operation Center Networking Dep.,Datacom Bureau China Telecom.,Beijing(100088),P.R.C +86-10-82078519/62359464/62367444(fax) --------------------------------------