I have run into a similar problem, although I don't get any "rcvd adjust" debug messages -- instead my scp transfers stall -- at a pretty predictable place too (not exactly, but to within a few megabytes). My problem ONLY started after I upgraded my kernel (and maybe some other things :s, from 2.6.19 to 2.6.33). My NFS transfers also started "stalling", for many minutes (5-15min usually), although they are retried, and eventually finish. Again, I don't think ANY of these problems ever happened with my old kernel for a couple years. During the stalls, netstat says the tcp connection is still ESTABLISHED, and when I Ctrl-C the stalled scp transfer, the sshd server logs a "Received disconnect" message. No other debug messages are shown for me. I'll try to get a tcpdump. On Fri, 12 Mar 2010 09:13:47 -0500, Matthew Case wrote: > First and foremost, thank you to everyone for your responses. I > checked the MTU on both sides and it's currently 1500 so I'm assuming > it's not a mismatch. My VPN is a pair of old Netscreen 5xp boxes, and > I can't find anything relating to MTU or packet size in the > configuration, but I'm still looking. > > Secondly, to answer your question John, There is no persistent > connection between the servers. I could feasibly set up an NFS share > between the two but I have a sneaking suspicion that if the problem > is some sort of packet mangling by the VPN during file transfers, the > actual mechanism used to transfer the file will be irrelevant. > However, I will set this up and test it and report back my results, > most likely next Monday. > > On 3/12/2010 3:41 AM, John Morrison wrote: > > Matt, > > > > If you are using ssh do you need to use scp as well? Or is just > > plain copy ok? > > > > On 10 March 2010 03:04, Darren Tucker<dtucker@xxxxxxxxxx> wrote: > > > >> Matthew Case wrote: > >> [...] > >> > >>> I've looked high and low and haven't really come up with anything > >>> definitive. Someone somewhere had mentioned fiddling with MTU > >>> settings, but I'm not really sure what that will accomplish as I > >>> am unfamiliar with what MTU is and does. If this question has > >>> been answered previously, I apologize ahead of time. Thanks! > >>> > >> This does sound like the MTU problem to which you refer. See > >> http://www.snailbook.com/faq/mtu-mismatch.auto.html for details. > >>
