LTSP/Localapps

From openSUSE

Running applications installed inside client chroot

LTSP provides a technology to run applications installed in the client also. This enables to launch many resource intensive applications such as Firefox to use resources(CPU/RAM) available in the powerful clients instead of running from the server.

LTSP5 on openSUSE includes Firefox as local app. It uses all the plugins installed on the server if the server is 32bit arch.

Open terminal and run the following to launch firefox:

 ltsp-localapps /usr/bin/firefox

For debugging purpose xterm can also be launched by running

 ltsp-localapps /usr/bin/xterm

Adding application into the image to run as localapps

To add more applications in the client chroot, add the the space separated list of package names in /etc/sysconfig/kiwi-ltsp as below and run kiwi-ltsp-setup -l to rebuild the image:

 LTSP_LOCALAPPS="flash-player kde4-kopete"

This will install flash-player, firefox flash plugin and kopete that can be run as local application from the client.

If you have RPM files with all dependencies and know that it does not require anything more you can do this short way of installing packages:

 kiwi-ltsp-setup -l1
 rpm -Uvh --nodeps --force --root=/srv/kiwi-ltsp-nfs *.rpm
 kiwi-ltsp-setup -l2

Next time only step 2 and 3 are required to add more packages.

Be warned that adding more applications in client chroot may degrade the performance.

Adding NVIDIA or ATI drivers into the image

If you wish to utilize 3D graphics capabilities or run Compiz on the clients, add the binary drivers for your hardware.

Add the following in /usr/share/kiwi/images/ltsp/suse-11.1/config.xml under extra-packages repository.

For ATI

       <repository type="rpm-md">
               <source path="http://www2.ati.com/suse/11.1/"/>
       </repository>

and inside /etc/sysconfig/kiwi-ltsp

 LTSP_LOCALAPPS="flash-player kde4-kopete x11-video-fglrxG01"

For NVIDIA the following in /usr/share/kiwi/images/ltsp/suse-11.1/config.xml under extra-packages repository

       <repository type="rpm-md">
               <source path="http://download.nvidia.com/opensuse/11.1/"/>
       </repository>

and inside /etc/sysconfig/kiwi-ltsp

 LTSP_LOCALAPPS="flash-player kde4-kopete x11-video-nvidiaG01"

Don't forget to run kiwi-ltsp-setup -l after making these changes.

Updating image

To get the latest updates in the image add rpm-md repository http://download.opensuse.org/update/11.1/ to config.xml as shown above.

Run kiwi-ltsp-setup -s. Please note that you need openSUSE 11.1 i586 DVD5 media/iso mounted at /mnt/11.1 before running kiwi-ltsp-setup.

If you are updating the kernel don't forget to modify also the files /usr/share/kiwi/image/*boot/*/config.xml, for example for a netboot for OpenSUSE 11.1 you need to modify /usr/share/kiwi/image/netboot/suse-11.1/config.xml and /usr/share/kiwi/image/ltsp/suse-11.1/config.xml. Also update the file /usr/share/kiwi/image/netboot/suse-11.0/.checksums.md5 or move it away.

How does Local Apps work?

The "ltsp-localapps" script sets xprop LTSP_COMMAND of root window. The "ltsplocalappsd" daemon sits listening for that xprop change, when it finds something it executes whatever is set as LTSP_COMMAND. The application run like this is the one installed in the client chroot and it uses local resources such as CPU and RAM.

See also

• Local apps blueprint on Ubuntu wiki