Package: x2goserver Version: 4.0.15-0~847 (x2goserver: 4.0.15-0~847~~ubuntu12.04.1 on Ubuntu Linux 12.04.4 LTS kernel 3.8.0-39-generic, x2goclient: 4.0.15-0~847~ubuntu14.04.1 on Ubuntu Linux 14.04 LTS kernel 3.14.3-031403-generic) Please note: I have labelled package x2goserver, but the bug is displayed on x2goclient even though I *think* the bug is in the server somewhere (see below).
Sometimes after an abrupt (e.g. CTRL-C, probably also network failure or laptop sleep/wake cycle) termination of x2goclient, I cannot reconnect to the server. I get errors such as the dreaded "Failure negotiating the session in stage '7'." and "Error: Wrong version or invalid session authentication cookie." instead. I am connecting through a proxy using ssh key-based authentication (using "Try auto-login" with "ssh-agent or default ssh key" on the proxy, although switching to password made no difference). I can connect with ssh through the proxy with no problem. I can *start* an x2go session with no problem. I can restart a session with no problem *provided I cleanly exit x2goclient* (e.g. by clicking on the close button on the window). If I exit x2goclient with a CTRL-C in the terminal, I cannot connect again. Note that I can connect to an NX session through the proxy without any problem and this does not have the same problem when CTRL-C. Steps to repeat: 1) On the client, open a new desktop on the server using x2goclient. (I am running KDE but I doubt it matters). 2) On the client, press CTRL-C to stop x2goclient. 3) On the client, try to reconnect -- it fails with errors (which are very hard to copy-paste as they go so fast, this is a bug in the GUI): ------------------------ NXPROXY - Version 3.5.0 Copyright (C) 2001, 2010 NoMachine. See http://www.nomachine.com/ for more information. Info: Proxy running in client mode with pid '7219'. Session: Starting session at 'Thu May 8 17:33:51 2014'. Info: Connecting to remote host 'localhost:31007'. Info: Connection to remote proxy 'localhost:31007' established. Error: The remote NX proxy closed the connection. Error: Failure negotiating the session in stage '7'. Error: Wrong version or invalid session authentication cookie. Session: Terminating session at 'Thu May 8 17:33:51 2014'. Session: Session terminated at 'Thu May 8 17:33:51 2014'. ------------------------ At this point the CPU usage of x2goclient jumps to 100% and I have to kill it (although the GUI continues to respond). This is just a minor annoyance at the moment. And in .x2go/SESSION_ID/sessions on the client, similar warnings: ------------------------ Loop: PANIC! No shutdown of proxy link performed by remote proxy. Loop: PANIC! The remote NX proxy closed the connection. Loop: PANIC! Failure negotiating the session in stage '7'. Loop: PANIC! Wrong version or invalid session authentication cookie. ------------------------ The server clearly detects the disconnect in its session.log, followed by “Display failure detected” errors on attempted reconnect: ----------------------- running as X2Go Agent NXAGENT - Version 3.5.0 Copyright (C) 2001, 2011 NoMachine. See http://www.nomachine.com/ for more information. Info: Agent running with pid '17414'. Session: Starting session at 'Fri May 9 14:44:26 2014'. Info: Proxy running in server mode with pid '17414'. Info: Waiting for connection from 'localhost' on port '30004'. Info: Accepted connection from '127.0.0.1'. Info: Connection with remote proxy completed. Info: Using ADSL link parameters 512/24/1/0. Info: Using agent parameters 5000/10/50/0/0. Info: Using cache parameters 4/4096KB/8192KB/8192KB. Info: Using pack method '16m-png-9' with session 'unix-kde-depth_24'. Info: Using ZLIB data compression 1/1/32. Info: Using ZLIB stream compression 4/4. Info: No suitable cache file found. Info: Listening to X11 connections on display ':51'. Info: Established X client connection. Info: Using shared memory parameters 1/1/1/2048K. Info: Using alpha channel in render extension. Info: Not using local device configuration changes. keyboard file created SessionPath not defined Session: Session started at 'Fri May 9 14:44:27 2014'. 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 'Fri May 9 14:44:44 2014'. Session: Suspending session at 'Fri May 9 14:44:44 2014'. Session: Session suspended at 'Fri May 9 14:44:44 2014'. Session: Resuming session at 'Fri May 9 14:45:11 2014'. Info: Proxy running in server mode with pid '17414'. Info: Waiting for connection from 'localhost' on port '30004'. Info: Aborting the procedure due to signal '1'. Session: Display failure detected at 'Fri May 9 14:45:27 2014'. Session: Suspending session at 'Fri May 9 14:45:27 2014'. Session: Session suspended at 'Fri May 9 14:45:27 2014'. -------------- In .x2go/C-SESSION_ID/session.log on the server, I now have the following text repeated over and over: Session: Suspending session at 'Fri May 9 15:08:49 2014'. [then hundreds or thousands of times, with later timestamps] The problem appears to be with the file /var/lib/x2go/x2go_sessions on the server. If I back this up *before* hitting CTRL-C on the client, then do the CTRL-C, then reinstate the backup, I can restart the session with no problems. Clearly this is beyond the ability of a normal user (without root on the server) and is not really a fix, even if it does work. It seems that there is a problem with the x2go_sessions file on the server being corrupted in some way when the remote session is abruptly disconnected. This is a failure bad enough for me to stop using x2go and go back to NX. * Backing up this file all the time is not an option. * Deleting this file and continuing, as suggested at http://bugs.x2go.org/cgi-bin/bugreport.cgi?bug=323, is not an option. * Note that unlink suggested in http://bugs.x2go.org/cgi-bin/bugreport.cgi?bug=323, there is no *server* crash. * I have tried the other options at http://bugs.x2go.org/cgi-bin/bugreport.cgi?bug=323, none apply here (e.g. permissions are fine). * The action that precipitates the problem is on the *client* side. * Note also that the network itself is not at fault: I can connect from a laptop in the same office (but on a different subnet) as the server, or from home to the proxy server direct. Same problem. * This seems similar to http://bugs.x2go.org/cgi-bin/bugreport.cgi?bug=101 but the fixes are more than a year ago and presumably (?) are in the latest x2goclient already. * No amount of calls to x2gosuspend-session or x2goresume-session on the appropriate session makes any difference. * If I suspend the session with x2gosuspend-session, attempting to connect *does* set the session into the “Running” state (just as x2goresume-session). The error seems to occur after this. Thanks for all your help x2go team, I hope we can fix this because I'd like to recommend x2go for my colleagues. Rob _______________________________________________ x2go-dev mailing list [email protected] http://lists.x2go.org/listinfo/x2go-dev
