ubuntu 12.10创建root根用户的方法

falldog

　　To get started, hit Ctrl+Alt+T, copy and paste this command into terminal and hit enter:
　　

　　
sudo passwd root
　　

　　Input current user’s password, then input a root password twice.  Typing in your password does not show in terminal, just blindly type in  your password and hit enter.

　　Enable Login as Root account in LightDM:
　　Root account won’t shown as a user in Ubuntu LightDM login screen, so  you need to manually type in username and password. To enable it:
　　Edit “/etc/lightdm/lightdm.conf” with this command:
　　

　　
gksudo gedit /etc/lightdm/lightdm.conf
　　

　　Then add this line to the end and save the file.

　　greeter-show-manual-login=true

　　Now restart your computer, choose Login and type in root and password to login as root.

　　Enjoy!