[X2Go-User] Can sessions of one user on different hosts collide?

Dear list,

On four debian wheezy machines I have X2Go server running without any problems since several weeks. There are about twenty users regularly connecting from their personal windows PCs. Usually at any given time on every server there are a handful of active/paused sessions running concurrently. The home directories are exported via NFS from a file server and shared among the X2Go servers.

Today, one user ('abbasi') told me, that since one or two weeks, he can only have one active connection to two of the servers (named 'lucas' and 'perrin') at a time, while before he could have active connections to both of them in parallel. Let me demonstrate an example with the error messages he gets. An extract of his session logs I put at the end of this mail.

Initially the user has one (LXDE) session running on both, 'lucas' and 'perrin', but only the connection to 'perrin' is open (at 17:35).

17:36 User resumes session on 'lucas', which lets the 'perrin' connection close.

17:38 User resumes session on 'perrin'. The x2go client maintaining the connection to 'lucas' yields an error message labeled 'X2Go - 50': "No response received from the remote server. Do you want to terminate the current session? (Yes/No)" With no answer given, a second error message pops up some seconds later: "The connection with the remote server was shut down. Please check the state of your network connection. (OK)".

Later on the user terminated LXDE on 'perrin' and logged in again, again loosing the connection to 'lucas'. Output of x2golistsessions_root is:

root@perrin:~# x2golistsessions_root |grep abbasi 23451|abbasi-50-1407426323_stDLXDE_dp32|50|perrin|S|2014-08-07T17:45:24| ab801814ece01b66cf5b9095ef08d537|134.99.208.12|30001|30002| 2014-08-07T17:50:07|abbasi|10878|30003|

root@lucas:/tmp# x2golistsessions_root |grep abbasi 31315|abbasi-50-1401721407_stDLXDE_dp32|50|lucas|S|2014-06-02T17:03:27| 2e6c06bec50eb7f89b1d165590a0a54d|134.99.208.12|30001|30002| 2014-08-07T17:45:27|abbasi|5715851|30003|

What got my attention is, the sessions on both servers coincidentally having the same <port> (50), <gr_port> (30001) and <snd_port> (30002). Could this lead to confusion for the 'peer proxy' mentioned in the 'Error:' line in the 'lucas'-log?

Looking forward to any suggestion, how to improve this situation. Thanks in advance!

Holger

root@lucas:/tmp/.x2go-abbasi# tail -f session-C- abbasi-50-1401721407_stDLXDE_dp32.log

Session: Resuming session at 'Thu Aug 7 17:36:15 2014'. Info: Proxy running in server mode with pid '31315'. Info: Waiting for connection from 'localhost' on port '30001'. Info: Accepted connection from '127.0.0.1'. Info: Connection with remote proxy completed. Info: Using LAN link parameters 1536/24/1/0. Info: Using agent parameters 5000/0/50/0/0. Info: Using pack method '16m-jpeg-9' with session 'unix-kde-depth_32'. Info: Not using NX delta compression. Info: Not using ZLIB data compression. Info: Not using ZLIB stream compression. Info: Not using a persistent cache. Info: Listening to X11 connections on display ':50'. Info: Established X client connection. Info: Using shared memory parameters 1/1/0/0K. nxagentInitAndCheckVisuals: WARNING! Ignoring not matched DirectColor visual. [... LINE ABOVE REPEATED 31 TIMES ...] Info: Not using local device configuration changes. keyboard file created SessionPath not defined Session: Session resumed at 'Thu Aug 7 17:36:17 2014'. Info: Screen [0] resized to geometry [800x600] fullscreen [0]. Info: Screen [0] resized to geometry [1440x848] fullscreen [0]. Error: Failure reading from the peer proxy. Error: Connection with remote peer broken. Error: Please check the state of your network and retry. Session: Display failure detected at 'Thu Aug 7 17:38:44 2014'. Session: Suspending session at 'Thu Aug 7 17:38:44 2014'. Session: Session suspended at 'Thu Aug 7 17:38:44 2014'. Session: Resuming session at 'Thu Aug 7 17:42:27 2014'. Info: Proxy running in server mode with pid '31315'. Info: Waiting for connection from 'localhost' on port '30001'. Info: Accepted connection from '127.0.0.1'. Info: Connection with remote proxy completed. Info: Using LAN link parameters 1536/24/1/0. Info: Using agent parameters 5000/0/50/0/0. Info: Using pack method '16m-jpeg-9' with session 'unix-kde-depth_32'. Info: Not using NX delta compression. Info: Not using ZLIB data compression. Info: Not using ZLIB stream compression. Info: Not using a persistent cache. Info: Listening to X11 connections on display ':50'. Info: Established X client connection. Info: Using shared memory parameters 1/1/0/0K. nxagentInitAndCheckVisuals: WARNING! Ignoring not matched DirectColor visual. [... LINE ABOVE REPEATED 31 TIMES ...] Info: Not using local device configuration changes. keyboard file created SessionPath not defined Session: Session resumed at 'Thu Aug 7 17:42:30 2014'. Info: Screen [0] resized to geometry [800x600] fullscreen [0]. Info: Screen [0] resized to geometry [1204x791] fullscreen [0]. Info: Screen [0] resized to geometry [1440x848] fullscreen [0]. Info: Screen [0] resized to geometry [1204x791] fullscreen [0]. Info: Screen [0] resized to geometry [1440x848] fullscreen [0]. Session: Suspending session at 'Thu Aug 7 17:43:11 2014'. Info: Waiting the cleanup timeout to complete. Session: Session suspended at 'Thu Aug 7 17:43:12 2014'. Session: Resuming session at 'Thu Aug 7 17:43:25 2014'. Info: Proxy running in server mode with pid '31315'. Info: Waiting for connection from 'localhost' on port '30001'. Info: Accepted connection from '127.0.0.1'. Info: Connection with remote proxy completed. Info: Using LAN link parameters 1536/24/1/0. Info: Using agent parameters 5000/0/50/0/0. Info: Using pack method '16m-jpeg-9' with session 'unix-kde-depth_32'. Info: Not using NX delta compression. Info: Not using ZLIB data compression. Info: Not using ZLIB stream compression. Info: Not using a persistent cache. Info: Listening to X11 connections on display ':50'. Info: Established X client connection. Info: Using shared memory parameters 1/1/0/0K. nxagentInitAndCheckVisuals: WARNING! Ignoring not matched DirectColor visual. [... LINE ABOVE REPEATED 31 TIMES ...] Info: Not using local device configuration changes. keyboard file created SessionPath not defined Session: Session resumed at 'Thu Aug 7 17:43:27 2014'. Info: Screen [0] resized to geometry [800x600] fullscreen [0]. Info: Screen [0] resized to geometry [784x562] fullscreen [0]. Info: Screen [0] resized to geometry [1440x848] fullscreen [0]. Info: Screen [0] resized to geometry [784x562] fullscreen [0]. Session: Suspending session at 'Thu Aug 7 17:43:44 2014'. Info: Waiting the cleanup timeout to complete. Session: Session suspended at 'Thu Aug 7 17:43:45 2014'.

root@perrin:/tmp/.x2go-abbasi# tail -f session-C- abbasi-50-1404746618_stDLXDE_dp32.log
Info: Using shared memory parameters 1/1/0/0K.
Info: Not using local device configuration changes.
keyboard file created
Session: Session resumed at 'Thu Aug 7 16:49:58 2014'.
Info: Screen [0] resized to geometry [800x600] fullscreen [0].
Info: Screen [0] resized to geometry [1440x848] fullscreen [0].
Session: Resuming session at 'Thu Aug 7 17:20:01 2014'.
Session: Display failure detected at 'Thu Aug 7 17:20:05 2014'.
Session: Suspending session at 'Thu Aug 7 17:20:05 2014'.
Session: Session suspended at 'Thu Aug 7 17:20:05 2014'.
Session: Resuming session at 'Thu Aug 7 17:30:08 2014'.
Info: Using shared memory parameters 1/1/0/0K. Info: Not using local device configuration changes. keyboard file created Session: Session resumed at 'Thu Aug 7 17:30:14 2014'. Info: Screen [0] resized to geometry [800x600] fullscreen [0]. Info: Screen [0] resized to geometry [1440x848] fullscreen [0]. Session: Suspending session at 'Thu Aug 7 17:35:59 2014'. Session: Session suspended at 'Thu Aug 7 17:36:00 2014'. Session: Resuming session at 'Thu Aug 7 17:38:43 2014'. Info: Using shared memory parameters 1/1/0/0K. Info: Not using local device configuration changes. keyboard file created Session: Session resumed at 'Thu Aug 7 17:38:49 2014'. Info: Screen [0] resized to geometry [800x600] fullscreen [0]. Session: Resuming session at 'Thu Aug 7 17:42:16 2014'. Session: Display failure detected at 'Thu Aug 7 17:42:20 2014'. Session: Suspending session at 'Thu Aug 7 17:42:20 2014'. Session: Session suspended at 'Thu Aug 7 17:42:20 2014'. Session: Resuming session at 'Thu Aug 7 17:44:04 2014'. Info: Using shared memory parameters 1/1/0/0K. Info: Not using local device configuration changes. keyboard file created Session: Session resumed at 'Thu Aug 7 17:44:10 2014'. Info: Screen [0] resized to geometry [800x600] fullscreen [0]. Info: Screen [0] resized to geometry [1440x848] fullscreen [0]. Session: Terminating session at 'Thu Aug 7 17:44:44 2014'. Session: Session terminated at 'Thu Aug 7 17:44:45 2014'.