XDMCP Thin Client Setup Guide

I just finished setting up a thin client that connects to my server. If you wish you can read more about it in the post. Here, however is a brief tutorial for setting up an XDMCP thin client. It covers the things that I had issues with, and gives enough information for a relatively linux command-line-savvy user to get through. It’s by no means aimed at newbies.

1. Step 1: Install Debian with as few packages as necessary.
   I installed Debian from floppy. You can find floppy disk images in /debian/dists/stable/main/installer-i386/current/images/floppy/ on whichever mirror you choose to use. The once you’ve written the floppy images (This tutorial doesn’t cover that, sorry,) you put in the boot floppy, and follow the prompts. It’s really not as difficult as the Debian documentation would have you believe.
2. Step 2: Install and configure X server.
   apt-get install x-window-system should do the trick for you. I believe it even automatically starts up the configuration interface. If it doesn’t, I’ve heard booting from a Knoppix disc and copying over /etc/X11/XFree86.conf file is a really quick and easy way. If you don’t mind editing it yourself, feel free. A good way to test if you’ve got yourself set up nicely is to just type ‘X’ (That’s a capital,) and see what happens. Ctrl+Alt+Backspace will kill the X server.
   Another thing to look out for is if the X server is starting up with the machine. This is bad, and you can stop it from doing so by editing /etc/inittab to read id:2:initdefault:. This starts the machine in runlevel 2, which is pretty much non-graphical multi user mode. Failing that, you might want to try removing GDM from startup if it’s installed. I’ve heard it can have the same effect.
3. Step 3 a: Make sure X can connect to another server.
   I sort of neglected to mention this earlier because I assumed everything would be fine (I did a net install, and regularly connect to my server via xdmcp). You want to first make sure you have network connectivity with the server. A good way to test is to use the ping tool.You then need to make sure you can connect to the X server. It’s not overly hard, but annoying if it doesn’t work. The command to connect is as follows. X -query YOUR_SERVER_IP
4. Step 3 b: Configure X to automatically connect to the server.
   Here’s where it got tricky for me. I sat up until half past 4 this morning trying to work it out. What you need to do is create an init script that will start the x server, instead of having it start automatically. To the end user there is no difference, but to the administrator this might seema little yukky. I’m fine with yukky though, especially seeing there’s no side effects.
   This init script was prepared by someone else, and I can’t damn well find the URL to reference them. They had some great information on setting up this kind of thing though. Essentially, what you want to do is create a file called /etc/init.d/xterm that will start the x server. You’ll want this file to look something like as follows:

   #! /bin/sh
   set -e
   
   case "$1" in
     start)
       start-stop-daemon --start --verbose --pidfile /var/run/xterm.pid --exec /usr/bin/X11/X -- -quiet -query YOUR_SERVER_IP_ADDRESS_OR_HOSTNAME &
       ;;
     stop)
       start-stop-daemon --stop --verbose --pidfile /var/run/xterm.pid --exec /usr/bin/X11/X
       ;;
     reload)
       # echo "Reloading $NAME configuration files"
       # start-stop-daemon --stop --signal 1 --quiet --pidfile /var/run/$NAME.pid --exec $DAEMON
       ;;
     *)
       # echo "Usage: /etc/init.d/$NAME {start|stop|reload}"
       echo "Usage: /etc/init.d/xterm {start|stop}"
       exit 1
       ;;
   esac
   
   exit 0

   You can download this script as a text file if it helps.
   This should be enough to start the x server. You can test it by typing /etc/init.d/xterm start If it doesn’t work, you may need to chmod 755 the file.

5. Step 4: Set the xterm service to autostart.
   Very easy, this step. Simply type as root: update-rc.d xterm defaults 99
6. Step 5: Profit.
   You should be done now. If something’s not working, feel free to drop me a mail, or post a comment. I’d like to help as mucha s possible.