This section discusses helpful tips for getting GDM working. In general, if you have a problem using GDM, you can submit a bug or send an email to the gdm-list mailing list. Information about how to do this is in the Introduction section of the document.

If GDM is failing to work properly, it is always a good idea to include debug information. To enable debugging, set the debug/Enable key to "true" in the <etc>/gdm/custom.conf file and restart GDM. Then use GDM to the point where it fails, and debug output will be sent to the system log file (<var>/log/messages or <var>/adm/messages depending on your Operating System). If you share this output with the GDM community via a bug report or email, please only include the GDM related debug information and not the entire file since it can be large. If you do not see any GDM syslog output, you may need to configure syslog (refer to the syslog man page).

7.1. GDM Will Not Start

There are a many problems that can cause GDM to fail to start, but this section will discuss a few common problems and how to approach tracking down a problem with GDM starting. Some problems will cause GDM to respond with an error message or dialog when it tries to start, but it can be difficult to track down problems when GDM fails silently.

First make sure that the Xserver is configured properly. The GDM configuration file contains a command in the [server-Standard] section that is used for starting the Xserver. Verify that this command works on your system. Running this command from the console should start the Xserver. If it fails, then the problem is likely with your Xserver configuration. Refer to your Xserver error log for an idea of what the problem may be. The problem may also be that your Xserver requires different command-line options. If so, then modify the Xserver command in the GDM configuration file so that it is correct for your system.

Also make sure that the /tmp directory has reasonable ownership and permissions, and that the machine's file system is not full. These problems will cause GDM to fail to start.