Introduction
Before we begin talking about how to run sudo command without password. Let’s briefly understand - What is a Sudo Command?
The sudo command in Linux stands for "superuser do" and is used to execute commands with elevated privileges. There are specific commands that can be run without entering the password.
Trusted users can use the sudo command to run applications as another user, by default the root user. Sudo is a command that you will use frequently if you spend a lot of time on the command line.
To provide a user sudo access, you usually have to add them to the sudo group established in the sudoers file. Members of the sudo group are granted sudo access on Debian, Ubuntu, and their derivatives, however, the sudo group on Red Hat-based systems like CentOS and Fedora is called wheel.
Before running a sudo command, each member of this group will be requested for their password. This offers an extra degree of protection and is the preferred method of granting users sudo capabilities.
In some cases, such as when running automated scripts, you may need to modify the sudoers file to allow specific users to perform sudo commands without being prompted for a password.
In this tutorial, you will run sudo command without password. We will also address a few FAQs on how to Run Sudo Command Without Password.
Adding User to the Sudoers File
The sudoers file stores information on a user's and group's sudo permissions.
You can change the sudoers file or add a configuration file to the /etc/sudoers.d directory to give the user sudo access. The sudoers file will include the files created in this directory.
It's a good idea to back up the current file before making any changes:
sudo cp /etc/sudoers{,.backup_$(date +%Y%m%d)}
Using the visudo command, open the /etc/sudoers file:
sudo visudo
Always utilize visudo when making modifications to the sudoers file. This command checks the file after editing and does not save the changes if there is a syntax error. If you use a text editor to open the file, a syntax error will result in the loss of sudo access.
The visudo command opens the /etc/sudoers file using the vim text editor on most systems. You can use another text editor if you don't have any expertise with vim. To change the editor to GNU nano, for example, type:
sudo EDITOR=nano visudo
Add the following line to the end of the file to allow the user "vega" to run any command with sudo without being prompted for a password:
vega ALL=(ALL) NOPASSWD:ALL
If you just want the user to be able to perform certain commands without having to enter a password, put the commands after the NOPASSWD keyword.
To enable only the mkdir and mv commands, for example, you would type:
vega ALL=(ALL) NOPASSWD:/bin/mkdir,/bin/mv
Save the file and quit the editor when you're finished.
Using /etc/sudoers.d
Instead of modifying the sudoers file, you can create a new file in the /etc/sudoers.d directory with the authorization rules. This approach makes sudo privilege control easier to maintain.
Create the following file in your text editor:
sudo nano /etc/sudoers.d/vega
You can name the file whatever you want, but it's usually a good idea to use the user's name as the file's name.
Add the same rule to the sudoers file as you did before:
vega ALL=(ALL) NOPASSWD:ALL
Now, save the file and quit the editor.
FAQs on How to run Sudo Command without Password
What is sudo and why is it commonly used in Linux?
sudo is a command that allows users to execute commands with elevated privileges or as another user, typically the root user.
How can I configure sudo to run commands without password authentication?
You can modify the sudoers file using the visudo command to specify which commands can be executed without password authentication.
What is the visudo command, and why should I use it to edit the sudoers file?
visudo is used to safely edit the sudoers file, maintaining its integrity and preventing accidental errors.
What precautions should I take when configuring sudo for passwordless commands?
You should be cautious when configuring sudo for passwordless commands, ensuring that only trusted and necessary commands are included.
How can I check if passwordless sudo execution is already enabled for my user?
You can check the sudoers file entry for your user and verify if the NOPASSWD option is present.
Can I still run sudo commands with a password even if passwordless execution is configured?
Yes, even if passwordless execution is configured, you can still run sudo commands with a password.
Is it possible to control passwordless execution on a per-command basis?
Yes, the sudoers file allows specifying individual commands or patterns for passwordless execution, offering fine-grained control.
Conclusion
In this tutorial, we have demonstrated how to change /etc/sudoers so that you can run sudo commands without having to input a password. This comes in handy when you have scripts that require a non-root user to perform administrative chores.
If you have any queries, please leave a comment below and we’ll be happy to respond to them.