Linux add a user using command line tools

Q. How do I add a new user using command line tools? What are command line option recommended.

A. You need to use useradd command, which is responsible for creating a new user or update default new user information

The useradd command creates a new user account using the values specified on the command line and the default values from the system. The new user account will be entered into the system files (/etc/passwd) as needed, the home directory (/home/username) will be created, and initial files copied, depending on the command line options.

Task: Add a user to the system

Syntax is as follows for useradd command:
useradd <username>

By default user account is locaked, you need to setup a new password:
passwd <username>

For example add a new user called tom and set password to jerry:
# adduser tom
# passwd tom


If you want to add a user to group read how to add a user user to group

List of common options:

• -c comment: Add a comment for the user
• -d home-directory: Create a new home-directory
• -e yyyy-mm-dd: Date for the account to be disabled
• -f days: Number of days after the password expires until the account is disabled. (If 0 is specified, the account is disabled immediately after the password expires. If -1 is specified, the account is not be disabled after the password expires.)
• -g group-name: Primary Group name or group number for the user’s default group (group name must exist)
• -G group-list: List of secondary additional (other than default) group names or group numbers, separated by commas, of which the user is a member (group name must exist)
• -m: Create the home directory
• -M: Do not create the home directory
• -s: User’s login shell (default /bin/bash)

To read all command line option type following command:
$ man adduser