Managing Users on Ubuntu: How to Add and Delete Users

User management is a fundamental task for any Ubuntu system administrator. Whether you’re setting up new accounts for team members or removing outdated ones, understanding how to add and delete users in Ubuntu ensures your system remains secure and organized.

This guide will walk you through the process of adding new users, deleting existing ones, and managing user privileges effectively.

Why Manage Users on Ubuntu?

Managing users allows you to:

Secure access to your system by giving individual accounts.
Control privileges with administrative roles or standard user access.
Organize resources by assigning specific permissions and directories.

How to Add a New User on Ubuntu

Adding a user involves creating a new account and setting up a home directory. Follow these simple steps:

1. Add a New User

Open the terminal and type: sudo adduser <username> Replace <username> with the desired name for the new account.
- The system will prompt you to set a password and provide optional details like the user’s full name.

2. Verify the User

Check the newly added user in the system:

cat /etc/passwd | grep <username>

The output confirms the user’s existence and details.

How to Delete an Existing User on Ubuntu

Removing a user is just as straightforward. You can choose to delete only the account or remove the associated home directory and files.

1. Delete a User Account

Use the following command to delete a user without removing their home directory:

sudo deluser <username>

2. Delete User and Their Home Directory

If you want to remove the user along with their files, run:

sudo deluser --remove-home <username>

3. Verify User Deletion

Confirm the user no longer exists: cat /etc/passwd | grep <username>

How to Manage User Privileges

1. Grant Administrative Privileges

Add the user to the sudo group:

sudo usermod -aG sudo <username>

2. Remove a User from a Group

To revoke privileges, remove the user from a group:

sudo deluser <username> groupname

Replace groupname with the group from which you want to remove the user.

Best Practices for User Management

Use Strong Passwords: Ensure users create secure passwords for added security.
Audit User Accounts Regularly: Periodically review accounts and remove unused ones.
Limit Administrative Access: Grant sudo privileges only to trusted users.

Troubleshooting Common Issues

Error: “User Already Exists”:
- Solution: Check if the username is already in use: cat /etc/passwd | grep <username>
Error: “Cannot Delete User Currently Logged In”:
- Solution: Ensure the user is logged out before deletion.
Home Directory Not Removed:
- Solution: Manually remove the directory if it still exists: sudo rm -rf /home/<username>

User management in Ubuntu is an essential skill for maintaining a secure and efficient system. By following the steps above, you can easily add new users, remove old accounts, and manage privileges to ensure your system remains organized and accessible.

Start practicing these commands today to enhance your Linux system administration skills!