GNOME Bugzilla – Bug 678363
100% packet loss caused by wrong estimated MTU
Last modified: 2015-05-27 20:05:43 UTC
Connection dried up by increased packet loss (100%). When i load many data at 2 MB/s via wifi the connection dried up. The connection was useless, and i had to reconnect. If i want to Download 80M i had to reconnect several times (~7). Consuming Audio or Video was very uncomfortable not to say impossible. After searching around i changed the MTU from 'automatic' to 1464 bytes. That is the value i found after experimenting with ping -Ms, thats the exact limit where everything works well. Here is some data: System: Linux gallifrey 3.2.0-25-generic #40-Ubuntu SMP Wed May 23 20:33:05 UTC 2012 i686 i686 i386 GNU/Linux Networkmanager: 0.9.4.0-0ubuntu4.1 Router: Speedport W 723V Firmware version: 1.24.000
Created attachment 216711 [details] Output of modinfo rt800pci The output of 'modinfo rt2800pci' is attached. Not sure if it is a bug of nm or the driver. Hope i do not forgot anything. :-? Maybe its related to: https://bugzilla.gnome.org/show_bug.cgi?id=603575
If reconnecting or modprobing the driver fixes the issue, that's probably rt2800pci bug. Try: modprobe rt2800pci nohwcrypt=1 See also http://rt2x00.serialmonkey.com/pipermail/users_rt2x00.serialmonkey.com/2012-January/004512.html When changing MTU helps, it probably means that your network setup requires lower MTU than default 1500. As you wrote, you can figure out optimal MTU via ping: $ pktsize=1516;for i in $( seq $pktsize -8 1340 ) ; do ping -M do -s $i -c 1 8.8.8.8; done
It was indeed a problem with the driver. I had to compile some version of the driver when i had the problem. But nowadays with a recent Distro like Debian 8 (Kernel 3.16) the problem is no more. Some update of the driver in the past fixed the problem. So i though i close this bug to keep the tracker clean.