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
- Open the ‘Run Application’ dialog by pressing:
Alt+F2
- Open/create the custom.conf file with gedit:
gksu gedit /etc/gdm/custom.conf
- Enter the configuration values that you want to override:
[daemon] AutomaticLoginEnable=true AutomaticLogin=lani
- 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.
Lani's Weblog 
Hi, Thanks for the tweak, it is great!
Just one note. How do I tell the computer about the default’s password? It tries to load my default but returns ‘authentication failed’. My guess is I need to add a line w/the password somewhere but I don’t know where or how. Thanks!
Hi miki!
I’m sorry but I have no clue. I only needed to make the changes that I’ve described here for it to work. Have you checked that you have spelled your username correctly? Also remember that linux logins are case sensitive.
I hope it works out for you.
Regards,
Lani
If you have configured your system use the encryption of home directories, GNOME will not start
properly with an auto-login. I have not confirmed this, but it seems that the password is required
to decrypt the home directory. Since no password is specified in the gdm config file, the home
directory is not decrypted and GNOME complains bitterly. I do not know what the solution is at
this time, or even if there is one. Sorry.
Thank you Paul for the heads up. I can see how that could be an issue. And you probably wouldn’t want auto login if you have such sensitive information that you would like to encrypt it. I also think, when you mention this, that the auto login isn’t possible in the installer together with the encryption option.
Pingback: Enable auto-login from SSH / remotely on Ubuntu 10.04 (GDM) | Hnygard.no