Adding and Removing Users with useradd, usermod, and userdel in Red Hat

Abdul Wahab Junaid

3 years ago

Adding and Removing Users with useradd, usermod, and userdel in Red Hat

The useradd command in Red Hat-based Linux distributions is used to create new user accounts on the system. It allows you to specify various parameters while creating a user account. Here’s a table with information and examples related to the useradd command:

Parameter	Description	Example
`-c, --comment <comment>`	Provide a comment or description for the user	`useradd -c "John Doe" john`
`-d, --home <directory>`	Set the home directory for the user	`useradd -d /home/john john`
`-g, --gid <group>`	Set the primary group for the user	`useradd -g users john`
`-G, --groups <groups>`	Specify additional groups for the user (comma-separated list)	`useradd -G developers,admins john`
`-m, --create-home`	Create the user’s home directory if it doesn’t exist	`useradd -m john`
`-s, --shell <shell>`	Set the login shell for the user	`useradd -s /bin/bash john`
`-u, --uid <UID>`	Set the user ID (UID) for the user	`useradd -u 1001 john`
`-p, --password <password>`	Set the encrypted password for the user	`useradd -p 'encrypted_password' john`
`username`	The username of the new user	`useradd newuser`

Examples:

Create a user named “john” with a comment:

Bash

   useradd -c "John Doe" john

Create a user named “john” with a specific home directory:

Bash

   useradd -d /home/john john

Create a user named “john” and assign them to the “users” primary group:

Bash

   useradd -g users john

Create a user named “john” and add them to the “developers” and “admins” groups:

Bash

   useradd -G developers,admins john

Create a user named “john” with a home directory and a default login shell:

Bash

   useradd -m -s /bin/bash john

Create a user named “john” with a specific UID (user ID):

Bash

   useradd -u 1001 john

Create a user named “john” with a pre-encrypted password:

Bash

   useradd -p 'encrypted_password' john

Create a user named “newuser”:

Bash

   useradd newuser

Please note that managing user accounts might require administrative privileges (sudo). Additionally, it’s a good practice to use the passwd command after creating a user to set their password interactively, as storing passwords in plain text or with reversible encryption is not recommended for security reasons.

Command	Description	Example
`useradd`	Create a new user account with specified parameters	`useradd -c "John Doe" -m -s /bin/bash john`
`usermod`	Modify existing user account attributes	`usermod -aG developers john`
`userdel`	Delete a user account and related files	`userdel -r john`

Examples:

useradd: Create a user named “john” with a comment, home directory, and default shell:

Bash

   useradd -c "John Doe" -m -s /bin/bash john

usermod: Add user “john” to the “developers” group:

Bash

   usermod -aG developers john

userdel: Delete the user “john” and remove their home directory and files:

Bash

   userdel -r john