Danbury Area Computer Society

by Drew Kwashnak

Do you have a number of older, slower machines that are still too good to throw away, but not powerful enough to run anything modern or useful? Does the idea of maintaining multiple computers with updates and patches which are becoming more and more rare for older systems not sound very appealing? Does knowing which system has the file or files you've been working on all month, season or year drive you crazy? Do your kids fight because they want to use your up-to-date (or least virus-laden) system?

I have found a solution for many of these issues and at September's Linux Special Interest Group (SIG) was able to demonstrate a taste of that solution; Linux Terminal Server Project (LTSP)[1] also known as "thin client" computing.

According to Wikipiedia [2]

"A thin client (or a lean client) is a network computer without a hard disk drive, which, in client and server applications, is designed to be especially small so that the bulk of the data processing occurs on the server."
and
"In contrast, a thick or fat client does as much processing as possible and passes only data for communications and storage to the server."

I installed Edubuntu[3] because it is made from Ubuntu[4] which is easy to use, setup and maintain, and Edubuntu is designed specifically to make setting it up as an LTSP server as easy as can be. After an hour and just over a dozen questions nicely documented on the Edubuntu website [3a], I had the server up and running on my Dell Optiplex GX 260 with 2.0 GHz Pentium 4 and 512 MB Ram and a gigabit Network Interface Card (NIC). You can set up an LTSP server with any Linux distribution such as RedHat[5], SuSE[6], Debian[7] or Ubuntu.

Edubuntu recommends at least 256MB RAM plus 128MB per user as sufficient to run office applications and a web browser for the server. The thin client requires a Pentium II with 48MB RAM and a 2MB display card while a Pentium II/300 with 64MB RAM and a 4MB display card or better is recommended. Naturally, the more CPU, RAM and bandwidth the server has, the faster all the systems will run, the more clients you can connect at one time and the smoother video playback and resource hogging applications will run.

Edubuntu is a version of Ubuntu Linux geared towards use for schools in classrooms, office and/or computer labs with a number of office applications and edutainment programs pre-installed. Just about any application for Windows or OS X has an equivalent application available in Linux and it is usually Free (free as in "free speech" as well as "free beer").
Some of the applications included are:
Firefox[8] browser, OpenOffice[9] office suite, Evolution[10] email and calendar client (like Outlook), Dia[11] flowcharting, Blender[12] 3D modeler, GIMP[13] image editor (like Photoshop), Scribus[14] desktop publisher, Totem[15] video player, Kino[16] digital video editor and much more. Keep in mind, all, except for Evolution, Totem and Kino, are available for Microsoft Windows too.

To get started once the operating system and LTSP are installed, hook your computers up to the network. Edubuntu and other LTSP websites recommend a system such as the illustration below.

Getting the server ready to receive requests requires booting the system up. You don't need to be logged into the computer for it to be ready. During the installation, you are asked for a super-user name and password. This account allows you to make up additional logins for the server, the users' permissions and modify the server's settings.

The thin client has to be set to boot to network. Most newer systems and network cards have built-in software that allows you to boot from the network. If not, you can create a floppy or CD which will allow the system to boot from network. You will find the option to boot from Network in the computer's BIOS under the Boot options. In the Boot options, you usually have an order in which you would boot (floppy, CDROM, hard disk drive). Make sure Netboot or the equivalent comes before HDD (hard disk drive) then Save & Exit.

Out of the three systems I tried to use as thin clients, two were easily successful. One of these two even tried to boot to the HDD first and when that failed, it got to the Network option and automatically detected and connected to the server. My one failure was my 7 year old PIII 500Mhz Sony, but that will be rectified with a bootable CD or floppy.

When running in a client, it feels as responsive as a fat client, despite the fact the thin clients are connected to the server through a 10/100Mbps ethernet adapter. I was also impressed when I found that when I connected my iPod Shuffle via USB to the client, the Rhythmbox music player opened up, which tells me it registered the USB device being attached.

When this is all set up at home, I am hoping to breathe new life into my 500Mhz system, allow the kids to both get on the computer at the same time, centralize our files and leave me with only one machine on which I have to run security updates once in a while. Additionally, I will only have one system I need to backup and be able to restore, not the 3 or 4 systems I would have to backup if they are all fat clients.

To get updates on how things are going and what I'm learning about thin client computing, come to the Linux SIG on the third Wednesday of every month at the DACS Resource Center. We are looking at setting up a thin client environment so attendees won't have to bring their own computer, or people with laptops won't have to install it on their system if they can boot their laptops onto the LTSP server.

For me, "thin is in".

Links for more information:

[1] http://www.ltsp.org
[2] http://en.wikipedia.org/wiki/Thin_client
[3] http://www.edubuntu.org
[3a] http://www.edubuntu.org/GettingStarted
[4] http://www.ubuntu.com
[5] http://www.redhat.com
[6] http://www.novell.com/linux/
[7] http://www.debian.com
[8] http://www.mozilla.com/en-US/
[9] http://www.OpenOffice.org
[10] http://www.gnome.org/projects/evolution/
[11] http://www.gnome.org/projects/dia/
[12] http://www.blender.org/
[13] http://www.gimp.org/
[14] http://www.scribus.net/
[15] http://www.gnome.org/projects/totem/
[16] http://www.kinodv.org/
[17] http://www.edubuntu.org/GettingStarted