sudo Command in Linux – FAQ

What is `sudo` in Linux?

Sudo is a command in Linux that allows users to run commands with privileges that only root user have. It helps users to do tasks with administrative power without logging in as the root user, though sometimes it can be risky.

Which Linux commands need `sudo` privileges?

There are many Linux commands that are needed to execute with sudo privileges such as networking commands, package management commands and system level commands. For example, commands that require sudo privileges to run are `yum`, `systemctl`, `mount`, `apt-get`, `fdisk` and `ifconfig`.

What can I run with sudo?

There are many Linux commands that require sudo privileges to run but one must remember to use it with caution as they can modify critical system configurations and files. To avoid consequences, we should check twice before running commands. Commands like:

• Installing a new package: `sudo apt-get install package_name`
• Updating the system: `sudo apt-get update && sudo apt-get upgrade`
• Modifying system configurations: `sudo nano /etc/fstab`
• Starting a system service: `sudo systemctl start service_name`
• Stopping a system service: `sudo systemctl stop service_name`
• Creating a new user account: `sudo useradd username`
• Changing file permissions: `sudo chmod 755 file_name`

What is difference between su and sudo command in Linux?

In Linux, the su (switch user) command enables users to log in as another user, often the root user, and access their files and settings. In contrast, the sudo command enables users to run certain commands with increased privileges without logging in as the root user. Sudo is a more secure method of granting temporary root privileges to users.

How do I give and take user sudo access in Linux?

In Linux we can give or take `sudo` access by adding or removing the username from the file called `sudores`. To add username to the sudoers we need to run `sudo visudo` command and edit the file and add the line that will give access to user. For example: “username ALL=(ALL:ALL) ALL” gives the user complete access to the sudo command.

And We can disable a user’s sudo access by using the same command “sudo visudo” which will be used to edit the sudoers file and remove the line that gives them sudo access. Once the line is deleted, the user will no longer be able to use the sudo command to execute privileged commands.

sudo (Super User DO) command in Linux is generally used as a prefix for some commands that only superusers are allowed to run. If you prefix any command with “sudo”, it will run that command with elevated privileges or in other words allow a user with proper permissions to execute a command as another user, such as the superuser. This is the equivalent of the “run as administrator” option in Windows. The option of sudo lets us have multiple administrators. 

These users who can use the sudo command need to have an entry in the sudoers file located at “/etc/sudoers”. Remember that to edit or view the sudoers file you have to use the sudo command. To edit the sudoers file it is recommended to use the “visudo” command. 

By default, sudo requires that users authenticate themselves with a password that is the user’s password, not the root password itself.