How to enable XDMCP without running X server on the console

INTRODUCTION

If the remote host is going to be used as XDMCP server, then you do not need to run the X server on the console. In other words, the remote server does not have to run the graphical user interface in order to accept XDMCP connections.

*This article requires remote server configuration. Administrator previlage may be required.

INFORMATION

Follow the instruction below to configure the remote host to accept XDMCP without running local X server.

To allow XDMCP connection on the remote host, a display manager ("gdm" or "kdm" but not both) must be running. However, by default, the display manager starts graphical user interface as well. We need to edit the gdm.conf file to prevent GUI from running. To do so:

1. Open /etc/X11/gdm/gdm.conf file.
2. Go to the [servers] section.

3. Comment out all definitions in the section by putting a # in front of each line: 
   

   [servers]
   #0=/usr/bin/X11/X
   #1=/usr/bin/X11/X

   
   

4. Restart "gdm" as root or restart the system.
   
   *If you are using KDE, edit /etc/X11/xdm/Xservers file instead.
   

Now, the Linux machine is configured to run X Window mode without local X server. It will just accept remote X terminals.