I have just installed Ubuntu Linux. But, what is the default root password? I can only login as a normal user. How do I login as root user?
This is the mystery for most users - you didn't set a root password, so what is it? The root user (also known as superuser), is a user on Ubuntu Linux and Unix-like systems with full administrative privileges (full access). So using root account for daily work can be very dangerous and you may damage your working system.
Ubuntu and root account
By default root account is locked under Ubuntu Linux. Therefore, you cannot login as root or use 'su -' command to become a superuser. To run all administrative command use sudo command. sudo allows a permitted user to execute a command as the superuser or another user. Ubuntu setup your default account (the one created during installation) to run all administrative commands.
For example create a new user called bar, you need to type sudo command as follows:
$ sudo adduser bar
When sudo asks for a password, you need to supply YOUR OWN password. In other words a root password is not needed. Here are few more examples.
Task: Start / stop / restart services stored in /etc/init.d/ directory
$ sudo /etc/init.d/ssh stop
$ sudo /etc/init.d/networking restart
Task: Avoid typing sudo each and every time
Note that this is not recommended until and unless you are an expert and aware of what you are typing:
$ sudo -i
Above command will start /bin/bash as a root shell so that you can enter a root user command without using sudo command.
How do I login as root user?
Open terminal and simply type the following command:
$ sudo bash
$ sudo -s
Supply your password and you will become a root user.