Ubuntu 9.10 alpha 3 comes with the latest GDM (The GNOME Display Manager, which is the default login manager shipped with Ubuntu). Unfortunately the latest version, 2.27.4, is an unstable version that still is heavily under development and still lacks a graphical configuration dialog.

So if you, like me, decided that you actually wanted to login automatically in GNOME instead of the manual login that you choose in the installation process, or vice versa. Well then it’s back to the configuration files. The default configuration values used by GDM is located in the XML file named ‘/etc/gdm/gdm.schema’. The documentation does however state that any changes to the default values should be made to the ‘/ect/gdm/custom.conf’ file, which is in keyfile format.

Configure GDM to auto login a specific user

1. Open the ‘Run Application’ dialog by pressing:

    Alt+F2

2. Open/create the custom.conf file with gedit:

   gksu gedit /etc/gdm/custom.conf

3. Enter the configuration values that you want to override:

   [daemon]
   AutomaticLoginEnable=true
   AutomaticLogin=lani

4. Reboot your system, and viola – you’re automatically logged in to GNOME! 🙂

Configuration explanation

Note that the [deamon] directive must be included in the file, it tells GDM in what section we want to override the keys. The AutomaticLoginEnable key  can be set to either true or false, to disable or enable the automatic login into GNOME. And finally the AutomaticLogin key should be set to the username of the user that should be loged into GNOME automatically, in the example above my username is lani.

References

GNOME Display Manager Reference Manual