How to Create a Sudo User on Ubuntu

In this tutorial we’ll create a sudo user on Ubuntu 18.04. The sudo command makes it possible for normal users to execute commands using administrator privileges, such as root.

You’ll often find that it’s recommended that you act as a sudo user, rather than root, when making changes to your system, as it’s more secure.

A few of the main reasons to use a sudo user instead of root are:

• 1. It prompts you for the password before major changes can happen. This helps as it can make you think of the consequences of what you’re doing.
• 2. sudo adds a log entry of the command(s) run (in /var/log/auth.log). You can check what commands were run, should something go wrong.
• 3. root is a default user on every server. Hackers know this and will attempt brute-force attacks on your server with the username root. They don’t know the usernames of your other users, however.
• 4. You don’t have to share your root account with someone that needs to do administrative tasks on your machine.
• 5. Authentication expires after a short time ( this can me edited ), so if you leave the terminal open, it won’t stay open indefinitely.

If you’d like to check all advantages and disadvantages of using a sudo user, instead of root, then you can find them on the Ubuntu community wiki page.

Steps to Creating a Sudo User

1. Log into your server via SSH

Log into your server as the root user.

If you are new to Linux, then follow this tutorial to connect to your server via SSH

2. Add a New User to Ubuntu

To add a new user, run the following command, replacing newuser with your desired user:

$ adduser newuser

The username you create should be in lowercase letters and with no special characters. If the user you create does not fit the criteria, then you’ll receive the following error:

adduser: Please enter a username matching the regular expression configured
via the NAME_REGEX[_SYSTEM] configuration variable.  Use the `--force-badname'
option to relax this check or reconfigure NAME_REGEX.

In my case, I’ll name my user vlad.

Once you run the command, you should see something like the following output:

Output

You will be prompted to enter a password you’d like to assign your new user. Please make sure that the password is a strong as possible.

New password:
Retype new password:
passwd: password updated successfully

After you’ve set your password, the command will create a home directory for the user, copy configuration files in the home folder and prompt you for your new user’s information. You can leave everything blank, and press Enter for each one to accept the defaults:

Changing the user information for vlad                                          
Enter the new value, or press ENTER for the default                             
        Full Name []:                                                           
        Room Number []:                                                         
        Work Phone []:                                                          
        Home Phone []:                                                          
        Other []:                                                               
Is the information correct? [Y/n] y

Once you’ve confirmed that the information you entered is correct, your user has been created and ready for use.

3. Add the New User to the Sudo Group

Now we’ll add our newly created user to the sudo group, thereby allowing it to execute commands with administrator privileges. To do this, run the following command, replacing vlad with the user you created:

$ usermod -aG sudo vlad

4. Login as the New Sudo User

Our new sudo user is all set up. Now all we have to do is switch to the new user account. We do this using the su command, as follows:

su - vlad

You may notice that once executed the command, your prompt will change and indicate that you are logged in as the new user, and not root.

Test the Sudo User

Let’s make sure the sudo user is set up correctly and test if it has sudo access. If you haven’t switched to it, do so now, replacing vlad with your created username:

su - vlad

Use sudo to run the whoami command. The first time you use sudo in a session, you’ll be prompted to enter the user password.

If your user has sudo access, then the output of the whoami command should be root.

How to Use sudo

To use sudo with your new user, just prefix any command you’d normally run with sudo and a space.

Let’s try it out by listing the contents of the /root directory, which is normally only accessible by the root user. To do this run:

$ sudo ls -la /root

But what if we don’t use sudo? Let’s try this by running the command again without the use of sudo:

$ ls -la /root

As mentioned before, only users with root privileges can access the /root directory, so we are denied accessing it this time.

Conclusion

Well done. You’ve learned how to create and use a new user with root privileges, which is an important and often overlooked step in securing your server.

If you’ve had any issues with this tutorial, then don’t hesitate to contact us or leave a comment below, and we’ll try to get back to you as soon as possible.

If you’re looking for high-performance servers at entry-level prices, then be sure to check out our KVM Linux Plans. Our offer starts at just $5.99/mo for 2GB RAM & 10GB SSD Linux VPS.