[systemd-devel] Centos 7 TigerVNC server crashing after unfriendly shutdowns

[Prof. Dr. Michael Schefczyk]

Dear All,

I like to implement virtualization via the KVM hypervisor on Centos 7 and - knowing that some people find that funny - use a server with GUI as the basis. To access the GUI within the LAN, I like to use TigerVNC server and set the user to root, since everything happens within the LAN and since all meaningful tasks using that route require root access anyway.

Unfortunately, TigerVNC does sometimes not survive unfriendly shutdowns which will occur, e.g., due to fencing. For more details, you may want to see this post https://www.centos.org/forums/viewtopic.php?f=48&t=50115

That renders the machine reachable only via other means (e.g. via KVM or SSH). Simple solutions, such as removing the relevant file under /tmp/.X11-unix or uninstalling and reinstalling tigervnc with a fresh configuration will not help. Sometimes it is possible to create a new vncserver service using a higher display number, but that obvouisly is not a proper way to resolve this. Much less desirable would be to install the whole server again hoping that it will not happen again qickly.

Please point me to a way to resolve this problem effectively.

A typical output of journalctl -xn is the enclosed below.

Regards

Michael

-- Logs begin at Do 2015-08-06 21:02:43 CEST, end at Do 2015-08-06 21:04:52 CEST. --
Aug 06 21:04:10 server1.schefczyk.local systemd[1]: vncserver@:1.service: control process exited, code=exited status=98
Aug 06 21:04:10 server1.schefczyk.local systemd[1]: Failed to start Remote desktop service (VNC).
-- Subject: Unit vncserver@:1.service has failed
-- Defined-By: systemd
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel
-- 
-- Unit vncserver@:1.service has failed.
-- 
-- The result is failed.
Aug 06 21:04:10 server1.schefczyk.local systemd[1]: Unit vncserver@:1.service entered failed state.
Aug 06 21:04:27 server1.schefczyk.local chronyd[1051]: Selected source 85.214.240.100
Aug 06 21:04:39 server1.schefczyk.local systemd[1]: Starting Stop Read-Ahead Data Collection...
-- Subject: Unit systemd-readahead-done.service has begun with start-up
-- Defined-By: systemd
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel
-- 
-- Unit systemd-readahead-done.service has begun starting up.
Aug 06 21:04:39 server1.schefczyk.local systemd[1]: Failed to reset devices.list on /machine.slice: Invalid argument
Aug 06 21:04:39 server1.schefczyk.local systemd[1]: Started Stop Read-Ahead Data Collection.
-- Subject: Unit systemd-readahead-done.service has finished start-up
-- Defined-By: systemd
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel
-- 
-- Unit systemd-readahead-done.service has finished starting up.
-- 
-- The start-up result is done.
Aug 06 21:04:40 server1.schefczyk.local sshd[4824]: Connection closed by 192.168.1.35 [preauth]
Aug 06 21:04:40 server1.schefczyk.local fprintd[4645]: ** Message: No devices in use, exit
Aug 06 21:04:52 server1.schefczyk.local gnome-session[2664]: (gnome-settings-daemon:2834): color-plugin-WARNING **: unable to get EDID for xrandr-VNC-
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