Err, with "-vvv" I get those exact same debug messages: "debug2: channel 0: rcvd adjust 131072" Lots of them. When trying to scp a 1G file to my server it consistently stalls around 10MB (give or take a few). What does that debug message mean, and why is it stalling, and why did it work with my earlier kernel? To be continued. On Mon, 22 Mar 2010 13:02:47 -0400, Dennis Nezic wrote: > 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. > > >>
