Well Ubuntu is different from most other Linux distributions in the way that it does not have a root account that is enabled by default. There are times when it is handy to have a root account so I’ll show you how to set it up.
1. Open the terminal and type:
sudo passwd root
2. You’ll get a prompt to “Enter new UNIX password”, enter the password you want for the root user and confirm it.
Now you can log out and log in as root.