I have Natty installed. Howto allow shutdown/restart if other user logged in another terminal, for example using CTRL-ALT-DEL? I've tried to add the following lines in /etc/sudoers: user ALL=(root)NOPASSWD:/sbin/reboot user ALL=(root)NOPASSWD:/sbin/halt user ALL=(root)NOPASSWD:/sbin/shutdown and sudo chmod 750 /sbin/shutdown sudo chmod 750 /sbin/reboot or create /etc/shutdown.allow but it doesn't help and I still get Gnome login mask.