By default, the Root account password is locked in Ubuntu and you will not able to login as Root directly or use the su command to become the Root user. The root user doesn’t have a password set. The steps to enable the root account is very simple. But it is not recommended because it may cause very serious trouble to your system because login as Root means you can do anything.
Issue this command to enable root login on Ubuntu 14.04. You will prompted for a new Unix password. Second password for confirmation :
sudo passwd root
login as: ehowstuff firstname.lastname@example.org's password: Welcome to Ubuntu 14.04 LTS (GNU/Linux 3.13.0-24-generic x86_64) * Documentation: https://help.ubuntu.com/ System information as of Sun Apr 27 23:49:57 MYT 2014 System load: 0.15 Processes: 68 Usage of /: 3.8% of 31.37GB Users logged in: 0 Memory usage: 3% IP address for eth0: 192.168.0.114 Swap usage: 0% Graph this data and manage this system at: https://landscape.canonical.com/ 4 packages can be updated. 1 update is a security update. Last login: Sun Apr 27 23:49:57 2014 ehowstuff@ubuntu14:~$ sudo passwd root [sudo] password for ehowstuff: Enter new UNIX password: Retype new UNIX password: passwd: password updated successfully ehowstuff@ubuntu14:~$