HowTo: Custom GDM Configuration For Auto Login, and Root Login from GDM.

Custom GDM Configuration For Auto And Timed Login — Fedora Unity Project

For internal VM's, an autologin on the console is convenient when you access the machines over VNC (protected network).

To use the gui for Root on a VM, it's also easier to allow log in as root (protected network).

cd /etc/pam.d
grep root gdm*
gdm:#auth required pam_succeed_if.so user != root quiet
gdm-fingerprint:#auth required pam_succeed_if.so user != root quiet
gdm-password:#auth required pam_succeed_if.so user != root quiet
gdm-smartcard:auth required pam_succeed_if.so user != root quiet

Then edit and comment out the "!=" root lines.

To allow autologin to an account from GDM on boot, you must boot runlevel 5 to use this...

vi /etc/gdm/custom.conf

[daemon]
AutomaticLoginEnable=true
AutomaticLogin=root

(root is dicey security wise, but so is an account with admin priviledges as on Ubuntu...)