Table of Contents
Introduction to adduser command
adduser is a command-line utility to create a new user in the Linux system. It is a friendlier frontend to the low-level tool 'useradd'. When adding a new user, it also creates the user directory under the /home directory.
How adduser command works
The default configuration file for adduser is /etc/adduser.conf.
adduser command will work according to the default value specified in adduser.conf file.
adduser command adds the details of the new user to the following files.
- /etc/passwd - It stores user account information.
- /etc/shadow - It contains the password information of users. The passwords are stored in an encrypted format.
- /etc/group - It stores group information.
Different examples to use adduser command
You can use
adduser command to add a normal user, system user, or user group in the Linux system. Only users with root privileges can add a user to the system. So, you will need to log in as a root user or use
sudo to execute
The general syntax of
adduser command is:
$ sudo adduser [option] user
Now, let's see some practical examples of
adduser command to add a user or group in the Linux system.
1. adduser command to add a new user
With this command, you can add a new user to the system. When adding a new user, you will be asked to enter some information.
$ sudo adduser user
/etc/passwd contains the user account information in the following format.
- Username: It is the login name for the user. The username should be between 1-32 characters.
- Password: It contains the user password in an encrypted format (x).
- User ID: Every user has a unique User Identification Number (UID). 1001 is the user ID of deepak.
- Group ID: It shows the primary group ID of a user. 1001 is the primary group ID of deepak.
- User detail: In between two colons, a GECOS or comment of a user will be displayed if added.
- Home Directory: The user's home directory. The default location is the /home directory.
- Login shell: The login shell for the user. The default login shell is /bin/bash.
2. Add a system user with adduser command
You can add a new system user using
--system option with
$ sudo adduser --system user
3. adduser command to create a new user group
--group option allows you to create a new user group in the system. The group is created without any users.
$ sudo adduser --group group
ubuntu@golinux:~$ sudo adduser --group linux Adding group `linux' (GID 1002) ... Done.
4. Add a system group with adduser command
We can use
--group option together to create a system group in the system. A system user with the same group name is also created.
$ sudo adduser --system --group group
5. adduser command to add a new user in different primary group
adduser command adds a new group for a user with the same username. To add a user in a different group, we can use
--ingroup option. The group should be already present in the system.
$ sudo adduser --ingroup GROUP user
6. adduser command to add a user with different home directory
adduser creates the user's home directory with username under the /home directory. We can create a user's home directory in a different location using
--home option. It also allows us to specify a different name for the user's home directory.
$ sudo adduser --home /directory/home_dir_name user
Here, we are adding a user 'sam' with its directory 'record' under the /snap directory.
7. adduser command to create a user without a home directory
adduser command automatically creates the user's home directory when adding a user. We can use
--no-create-home option to add a user without its home directory.
$ sudo adduser --no-create-home user
As we can see, the default home directory is /home/elliot but it is not created.
8. Add a user with specific user ID with adduser command
Every user has a unique user ID in the Linux system. By default,
adduser command assigns the next available user ID to a new user. We can use
--uid option to add a new user with a custom user ID.
$ sudo adduser -u userID user
$ sudo adduser --uid userID user
The user chris is assigned with a custom user ID 4567.
9. adduser command to create a user with specific group ID
We have already seen that the adduser command creates a new group with a user name and adds a user to that group. To add a user to a different group, we can use
--gid option. The group should be already present in the system.
$ sudo adduser --gid groupID user
10. adduser command to add a user with a custom login shell
adduser command selects the default login shell specified by DSHELL variable in /etc/adduser.conf. The default login shell is /bin/bash. To use a different login shell, we can use
--shell option as shown below.
$ sudo adduser --shell SHELL user
11. Add an existing user to an existing group with adduser command
Instead of adding a new user, you can also add an existing user to an existing group using
$ sudo adduser user group
12. adduser command to create a user with a disabled login
--disabled-login option does not ask to set a password for a new user. The user won't be able to use the account until the password is set.
$ sudo adduser --disabled-login user
We can set or change the user password in the Linux system by using the following
ubuntu@golinux:~$ sudo passwd maxim New password: Retype new password: passwd: password updated successfully
13. Create a user without password using adduser command
--disabled-password also does not ask to set a password when adding a user. It is similar to the above command
$ sudo adduser --disabled-password user
14. adduser command to add a user with a GECOS or comment
A GECOS or comment field is generally used for keeping the information related to the user. We can use
--gecos option to add a GECOS or comment when creating a new user.
$ sudo adduser --gecos GECOS user
15. adduser command to print the debug information
We can use
--debug option to print the information in a verbose mode. It is useful when debugging the adduser.
$ sudo adduser --debug user
16. Hide informational messages with adduser command
--quiet option hides the informational messages in the output. It does not hide warnings and errors.
$ sudo adduser --quiet user
adduser is a useful command to add a user or group in the Linux system. We hope you have learned to use
adduser command from this article. If you still have any confusion, please feel free to ask us in the comment section.