Q. How do I enable root login under Fedora 10 Gnome GUI login screen / manager?
A. Fedora 10 uses pam module called pam_succeed_if.so. This module is designed to succeed or fail authentication based on characteristics of the account belonging to the user being authenticated. One use is to select whether to load other modules based on this test. This module blocks root login using GUI.
Login as root
Log in as normal user
Then open GUI terminal (bash prompt) and type the following command to become root user:
$ su -
Fedora 10 update GDM config to allow root login
Type your root password. Next, make a backup of /etc/pam.d/gdm, enter:
cp /etc/pam.d/gdm /root
Now open /etc/pam.d/gdm using gedit or vi text editor, enter:
Alternatively, you can do everything in a one command:
su -c 'gedit /etc/pam.d/gdm'
Find line that read as follows:
auth required pam_succeed_if.so user != root quiet
Remove or comment out line by prefixing #.
# auth required pam_succeed_if.so user != root quiet
Save and close the file. Logout from terminal and from GUI itself. Now you should be able login as root user using GDM GUI login manager.