Superuser Privileges

The “root” user is the superuser account in Linux systems. Users can temporarily gain root privileges using the sudo command, which requires authenticaion from the user’s account. The user will only have sudo privileges if the account is listed in the sudoers file.

Adding a User to the Sudoers File

To add a user to the sudoers file, you will need to edit the /etc/sudoers file. As best practice, you should use the visudo command to open and edit this file. Typically, you’ll add a line specifying the user and their privileges, such as username ALL=(ALL:ALL) ALL. For more information about the sudoers file, visit this resource.

Using the sudo Command

The sudo command allows a regular user to execute specific commands with root (superuser) privileges. Unlike switching to root entirely, sudo elevates privileges only for the command being run, making it a safe and auditable method of performing administatrive tasks.

How sudo Works

When a user runs a command with sudo, they will be propmted to enter their own password. If the user is listed in the /etc/sudoers file, the elevated command will run.

Example:

sudo apt update

Using the su Command

It is highly recommended that GUI interfaces not be run as root, as this can easily lead to disaster. It is best to be logged in as a normal unprivileged user and to only use root as required. Many commands can only be run as the root user. To run these commands, use the su command (substitute user).

The su command takes the following format:

su - <user>

or

su <user>

most commonly you will use su to become the root user:

su - root

or

su root

If no username is specified, the root user is automatically assumed. For more information on su checkout this resource or visit the su man pages.

Resources