This page was first tested on Ubuntu versions 8.04, The same directions also work on Lucid. Considering the package consists of shell scripts it should work on any version.
If you find this information applicable to additional versions/releases, please edit this page and modify this header to reflect that. Please also include any necessary modifications for this information to apply to the additional versions.
In Ubuntu 8.10 and above this functionality is partly integrated in LTSP, to use it, you add the option LDM_LIMIT_ONE_SESSION = True in your lts.conf file.
Note that LDM_LIMIT_ONE_SESSION kills leftover processes only when the user logs in again, while gnome-watchdog kills them on logout.
Video tutorial available at http://www.youtube.com/watch?v=9Q9vkYs9bWU
This page is dedicated to installing and configuring the gnome-watchdog package.
gnome-watchdog is a script that launches upon user login from an LTSP thin-client. It monitors the status of their "gnome-panel" process, and if it dies, waits an amount of time, and kills the remaining process. The idea is that when a user logs out, their gnome-panel process cleanly exits, but other, misbehaving applications might not (such as Firefox, or Open Office in some cases I've personally experienced). It logs everything it does to syslog, which makes debugging/tracking what it kills very useful (for, say, reporting commonly stale processes to their respective package maintainers so they can fix them).
To install gnome-watchdog, download the package from the following link: http://logicalnetworking.net/other/gnome-watchdog_0.9.2_i386.deb
Install it (and gtkdialog, which it requires) on your LTSP server:
sudo apt-get install gtkdialog sudo dpkg -i gnome-watchdog_0.9.2_i386.deb
Note: On amd64 installations you will need to force installation of the i386 package. Do so with the following command:
sudo dpkg --force-architecture -i gnome-watchdog_0.9.2_i386.deb
In the case that gnome-panel doesn't cleanly exit (such as if the thin-client crashes), gnome-watchdog will do nothing - unless you create the following file, which will cause gnome-watchdog to check the status of the logging-in user's gnome-panel process, and give them the option to kill their previous session:
sudo touch /etc/check_previous_login
Please see /usr/share/gnome-watchdog/README for further information regarding this package.
Thanks to firstname.lastname@example.org for creating this great package!