"Exterminate all the Brutes"

I am amazed by how easy it has become to set up a server for an entire network of thin clients, provided that you use Edubuntu. Before the LTSP project (and its incorporation into the Edubuntu GNU/Linux distribution), it used to be very hard to set up a network for thin clients. I personally sweated bullets trying to get myriad flimsy network settings right, debugging problems with the TFTP server and battling countless other horrors before successfully booting my first thin client.

Today, all you need is one Edubuntu CD. Finished.

The standard installation of Edubuntu includes a fully working LTSP-based terminal server for thin clients, and it’s already set up and enabled by default. All you need to take care of is that your network has the address 192.168.0.0, i.e. your clients will receive addresses starting with 192.168.0 from your Edubuntu server, which is expected to be 192.168.0.1. If your network situation is different, simply edit /etc/ltsp/dhcpd.conf so that the DHCP server supplies addresses that match your setup. The IP address of the server may also have to be changed in this step. Also, depending on your net, you may want to add a second network card to your server and set it all up for forwarding. With forwarding, all thin clients on your network can access the Internet. You can then go on to more advanced setups, such as limiting the Internet access of thin clients to certain times of day, blocking certain bandwidth-heavy sites or installing the Squid caching proxy to speed up access to frequently used websites while lowering the impact on your Internet connection.

But all in all it’s breathtakingly simple!

I’ve tested this setup using both types of Fujitsu-Siemens thin clients that Alex took with him to Malawi (Futro S300 and Futro B220), and both worked. You can even have multiple users logged into a single thin client at the same time 🙂 I will do some more testing when I find the time (a scarce resource), so that I can give Alex hints in case we discover a few stumbling blocks.

This is fun! I hope you can replicate this setup at The Polytechnic and profit from the experience.

A note about the different models of thin clients

With this setup, I recommend using the S300 thin clients Alex brought. They boot faster and the display driver has hardware-acceleration — all in all everything feels much more fluid! Don’t be alarmed if your screen goes black in the beginning of the boot process. For some reason, the client switches into a strange video mode that some monitors don’t like. After a while, the Edubuntu login screen will come up after all.

The older B220 clients boot slower, have no video acceleration and seem to be having problems displaying certain icons. I’m quite sure it’s a problem with the video driver there. I might investigate that, but because Alex brought mostly brand new S300 clients, I think this will be less of an issue for you. Just use the S300 where it really matters (on student workplaces) and stick to the B220 where the speed and accuracy of the display is not that important, for example at the library administrator’s workstation. The display works well enough to set up users and accounts and to run a shell 🙂

By the way, the illustration you see next to this text is my attempt to draw a diagram of how a terminal server roughly works. You can download the original OpenDocument version or a PDF, too. Feel free to share and edit them, they are licensed under the Creative Commons Attribution-ShareAlike license which gives you that freedom.

This entry was posted on Monday, October 30th, 2006 at 10:26 AM and is filed under Malawi, Technology. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.