Add A User Manually In Linux

Posted : admin On 10/6/2021
  1. Linux Add User Password
  2. Linux Ubuntu Add A User
  3. Add A User In Linux

On Unix-like operating systems, the useradd command creates a new user or sets the default information for new users.

This document covers the Linux version of useradd.

  • Dec 09, 2016  To add/create a new user, all you’ve to follow the command ‘ useradd ‘ or ‘ adduser ‘ with ‘username’. The ‘username’ is a user login name, that is used by user to login into the system. Only one user can be added and that username must be unique (different from other username already exists on.
  • Learn More About Adding Users and Groups to Linux When working in Linux, there are a number of options you have for creating users and groups. For instance, you could just go into /etc/passwd directly and add a user there, but unless you are familiar with file editors and putting a lock on, you should work with the commands to avoid corruption.
  • Nov 30, 2016  Introduction Linux is a multiuser operating system. In a multiuser environment, it is a common administration task to create new users, modify existing users, or remove users. For ease of access management, users are assigned to groups. Creating, deleting, and modifying groups is also another common administration task. This guide covers the basics of user.

Description

To create a user, you need to add information about the user to the user database, and create a home directory for him. It may also be necessary to educate the user, and set up a suitable initial environment for him. Most Linux distributions come with a program for creating accounts. There are several such programs available. Nov 05, 2018  In this article, we will describe how to change a user’s shell in Linux. The shell is a program that accepts and interprets commands; there are several shells such as bash, sh, ksh, zsh, fish and many other lesser known shells available on Linux.

useradd is a low-level utility for adding users to a system. In general, the more friendly adduser should be used instead.

Your operating system may come with a slightly different version of useradd; check your documentation before using it to create new accounts. This documentation refers to some options frequently used on Debian-based variants of Linux, but is representative of useradd's general use.

When invoked without the -D option, the useradd command creates a new user account using the values specified on the command line plus the default values from the system. Depending on command line options, the useradd command will update system files and may also create the new user's home directory and copy initial files.

By default, a group will also be created for the new user (see the -g, -N, -U options, and the USERGROUPS_ENAB variable, below).

Syntax

Options

-c, --commentCOMMENTCOMMENT can be any text string. It is generally a short description of the login, and is currently used as the field for the user's full name.
-d, --homeHOME_DIRThe new user will be created using HOME_DIR as the value for the user's login directory. The default is to append the LOGIN name to BASE_DIR and use that as the login directory name. The directory HOME_DIR does not have to exist but will not be created if it is missing.
-D, --defaultsSet new default values. See the section on Changing New User Default Values, below.
-e, --expiredateEXPIRE_DATEThe date on which the user account will be disabled. The date is specified in the format YYYY-MM-DD.
If not specified, useradd will use the default expiry date specified by the EXPIRE variable in /etc/default/useradd, or an empty string (no expiry) by default.
-f, --inactiveINACTIVEThe number of days after a password expires until the account is permanently disabled. A value of 0 disables the account as soon as the password has expired, and a value of -1 disables the feature.
If not specified, useradd will use the default inactivity period specified by the INACTIVE variable in /etc/default/useradd, or -1 by default.
-g, --gidGROUPThe group name or number of the user's initial login group. The group name must exist. A group number must refer to an already existing group.
If not specified, the behavior of useradd will depend on the USERGROUPS_ENAB variable in /etc/login.defs. If this variable is set to yes (or -U/--user-group is specified on the command line), a group will be created for the user, with the same name as her loginname. If the variable is set to no (or -N/--no-user-group is specified on the command line), useradd will set the primary group of the new user to the value specified by the GROUP variable in /etc/default/useradd, or 100 by default.
-G, --groupsGROUP1[,GROUP2,...[,GROUPN]]]A list of groups containing the user as a member. Each group is separated from the next by a comma, with no intervening whitespace. The groups are subject to the same restrictions as the group given with the -g option. The default is for the user to belong only to the initial group.
-h, --helpDisplay a help message, and exit.
-k, --skelSKEL_DIRSKEL_DIR is the skeleton directory, which contains files and directories to be copied in the user's home directory, when the home directory is created by useradd.
This option is only valid if the -m (or --create-home) option is specified.
If this option is not set, the skeleton directory is defined by the SKEL variable in /etc/default/useradd or, by default, /etc/skel.
If possible, the ACL and extended attributes are copied.
-K, --keyKEY=VALUEOverrides /etc/login.defs defaults (UID_MIN, UID_MAX, UMASK, PASS_MAX_DAYS and others).
Example: -KPASS_MAX_DAYS=-1 can be used when creating system account to turn off password aging, even though system account has no password at all. Multiple -K options can be specified, for example: -K UID_MIN=100 -K UID_MAX=499
-l, --no-log-initDo not add the user to the lastlog and faillog databases.
By default, the user's entries in the lastlog and faillog databases are resetted to avoid reusing the entry from a previously deleted user.
For the compatibility with previous versions of useradd, the -O option is also supported for this purpose.
-m, --create-homeCreate the user's home directory if it does not exist. The files and directories contained in the skeleton directory (which can be defined with the -k option) will be copied to the home directory.
By default, if this option is not specified and CREATE_HOME is not enabled, no home directories are created.
-MDo no create the user's home directory, even if the system wide setting from /etc/login.defs (CREATE_HOME) is set to yes.
-N, --no-user-groupDo not create a group with the same name as the user, but add the user to the group specified by the -g option or by the GROUP variable in /etc/default/useradd.
The default behavior (if the -g, -N, and -U options are not specified) is defined by the USERGROUPS_ENAB variable in /etc/login.defs.
-o, --non-uniqueAllow the creation of a user account with a duplicate (non-unique) UID.
This option is only valid in combination with the -u option.
-p, --passwordPASSWORDThe encrypted password, as returned by crypt. The default is to disable the password.
Note: This option is not recommended because the password (or encrypted password) will be visible by users listing the processes (for example, with the ps command).
You should make sure the password respects the system's password policy.
-r, --systemCreate a system account.
System users will be created with no aging information in /etc/shadow, and their numeric identifiers are chosen in the SYS_UID_MIN-SYS_UID_MAX range, defined in /etc/login.defs, instead of UID_MIN-UID_MAX (and their GID counterparts for the creation of groups).
Note that useradd will not create a home directory for such an user, regardless of the default setting in /etc/login.defs (CREATE_HOME). You have to specify the -m options if you want a home directory for a system account to be created.
-R, --rootCHROOT_DIRApply changes in the CHROOT_DIR directory and use the configuration files from the CHROOT_DIR directory.
-s, --shellSHELLThe name of the user's login shell. The default is to leave this field blank, which causes the system to select the default login shell specified by the SHELL variable in /etc/default/useradd, or an empty string by default.
-u, --uidUIDThe numerical value of the user's ID. This value must be unique, unless the -o option is used. The value must be non-negative. The default is to use the smallest ID value greater than or equal to UID_MIN and greater than every other user.
See also the -r option and the UID_MAX description.
-U, --user-groupCreate a group with the same name as the user, and add the user to this group.
The default behavior (if the -g, -N, and -U options are not specified) is defined by the USERGROUPS_ENAB variable in /etc/login.defs.
-Z, --selinux-userSEUSERThe SELinux user for the user's login. The default is to leave this field blank, which causes the system to select the default SELinux user.

Changing New User Default Values

When invoked with only the -D option, useradd displays the current default values. When invoked with -D plus other options, useradd will update the default values for the specified options.

Valid default-changing options are:

-b, --base-dirBASE_DIRThe pathprefix for a new user's home directory. The user's name will be affixed to the end of BASE_DIR to form the new user's home directory name, if the -d option is not used when creating a new account.
This option sets the HOME variable in /etc/default/useradd.
-e, --expiredateEXPIRE_DATEThe date on which the user account is disabled.
This option sets the EXPIRE variable in /etc/default/useradd.
-f, --inactiveINACTIVEThe number of days after a password has expired before the account will be disabled.
This option sets the INACTIVE variable in /etc/default/useradd.
-g, --gidGROUPThe group name or ID for a new user's initial group (when the -N/--no-user-group is used or when the USERGROUPS_ENAB variable is set to no in /etc/login.defs). The named group must exist, and a numerical group ID must have an existing entry.
This option sets the GROUP variable in /etc/default/useradd.
-s, --shellSHELLThe name of a new user's login shell.
This option sets the SHELL variable in /etc/default/useradd.

Notes

The system administrator is responsible for placing the default user files in the /etc/skel/ directory (or any other skeleton directory specified in /etc/default/useradd or on the command line).

Caveats

You may not add a user to a NIS or LDAP group. This must be performed on the corresponding server.

Similarly, if the username already exists in an external user database such as NIS or LDAP, useradd will deny the user account creation request.

It is usually recommended to only use usernames that begin with a lower case letter or an underscore, followed by lower case letters, digits, underscores, or dashes. They can end with a dollar sign. The regular expression which describes a valid username is:

[a-z_][a-z0-9_-]*[$]?

The only constraints are that usernames must neither start with a dash ('-') nor plus ('+') nor tilde ('~') nor contain a colon (':'), a comma (','), or a whitespace (space: ' ', end of line: 'n', tab: 't', etc.). Note that using a slash ('/') may break the default algorithm for the definition of the user's home directory.

Usernames may only be up to 32 characters long.

Configuration

The following configuration variables in /etc/login.defs change the behavior of this tool:

nametypedescription
CREATE_HOMEbooleanIndicate if a home directory should be created by default for new users.
This setting does not apply to system users, and can be overridden on the command line.
GID_MAX, GID_MINnumberRange of group IDs used for the creation of regular groups by useradd, groupadd, or newusers.
The default value for GID_MIN is 1000; the default for GID_MAX is 60000.
MAIL_DIRstringThe mail spool directory. This is needed to manipulate the mailbox when its corresponding user account is modified or deleted. If not specified, a compile-time default is used.
MAIL_FILEstringDefines the location of the users mail spool files relatively to their home directory.

The MAIL_DIR and MAIL_FILE variables are used by useradd, usermod, and userdel to create, move, or delete the user's mail spool.

MAX_MEMBERS_PER_GROUPnumberMaximum members per group entry. When the maximum is reached, a new group entry (line) is started in /etc/group (with the same name, same password, and same group ID).
The default value is 0, meaning that there are no limits in the number of members in a group.
This feature (split group) can help to limit the length of lines in the group file. This is useful to make sure that lines for NIS groups are not larger than 1024 characters.
If you need to enforce such limit, you can use 25.
Note: split groups may not be supported by all tools, even advanced tools like the Shadow toolsuite. You should not use this variable unless you really need it.
PASS_MAX_DAYSnumberThe maximum number of days a password may be used. If the password is older than this, a password change will be forced. If not specified, -1 will be assumed (which disables the restriction).
PASS_MIN_DAYSnumberThe minimum number of days allowed between password changes. Any password changes attempted sooner than this will be rejected. If not specified, -1 will be assumed (which disables the restriction).
PASS_WARN_AGEnumberThe number of days warning given before a password expires. A zero means warning is given only upon the day of expiration, a negative value means no warning is given. If not specified, no warning will be provided.
SYS_GID_MAX, SYS_GID_MINnumberRange of group IDs used for the creation of system groups by useradd, groupadd, or newusers.
The default value for SYS_GID_MIN is 101; the default value for SYS_GID_MAX is GID_MIN minus 1.
SYS_UID_MAX, SYS_UID_MINnumberRange of user IDs used for the creation of system users by useradd or newusers.
The default value for SYS_UID_MIN is 101; the default value of SYS_UID_MAX is UID_MIN minus 1.
UID_MAX, UID_MINnumberRange of user IDs used for the creation of regular users by useradd or newusers.
The default value for UID_MIN (resp. UID_MAX) is 1000 (resp. 60000).
UMASKnumberThe file mode creation mask is initialized to this value. If not specified, the mask will be initialized to 022. useradd and newusers use this mask to set the mode of the home directory they create. It is also used by pam_umask as the default umask value.
USERGROUPS_ENABbooleanIf set to yes, userdel will remove the user's group if it contains no more members, and useradd will create by default a group with the name of the user.

Files

/etc/passwdUser account information.
/etc/shadowSecure user account information.
/etc/groupGroup account information.
/etc/gshadowSecure group account information.
/etc/default/useraddDefault values for account creation.
/etc/skel/Directory containing default files.
/etc/login.defsShadow password suite configuration.

Exit Status

useradd exits with the following status, depending on what occurred:

0Everything was completed successfully.
1Couldn't update the password file.
2The syntax of the command was invalid.
3One or more options were given an invalid argument.
4User ID is already in use, and -o was not specified.
6Specified group doesn't exist.
9Username already in use.
10Couldn't update the group file.
12Couldn't create the home directory.
14Couldn't update SE Linux user mapping.

Examples

Linux Add User Password

Note

For these commands to work you must have root privileges.

Displays the defaults for new users. Output resembles the following:

Creates newperson as a new user. Once the new user has been added, you would need to use the passwd command to assign a password to the account.

Once a user has been created, you can modify any of the user settings, such as the user's home directory, using the usermod command.

Related commands

groupadd — Add a group to the system.
passwd — Change a user's password.
userdel — Remove a user from the system.
usermod — Modify a user's account.

-->

There are several scenarios in which you may not be able (or want) to, install WSL Linux distros via the Microsoft Store. Specifically, you may be running a Windows Server or Long-Term Servicing (LTSC) desktop OS SKU that doesn't support Microsoft Store, or your corporate network policies and/or admins to not permit Microsoft Store usage in your environment.

In these cases, while WSL itself is available, how do you download and install Linux distros in WSL if you can't access the store?

Note: Command-line shell environments including Cmd, PowerShell, and Linux/WSL distros are not permitted to run on Windows 10 S Mode. This restriction exists in order to ensure the integrity and safety goals that S Mode delivers: Read this post for more information.

Downloading distros

If the Microsoft Store app is not available, you can download and manually install Linux distros by clicking these links:

This will cause the <distro>.appx packages to download to a folder of your choosing. Follow the installation instructions to install your downloaded distro(s).

Downloading distros via the command line

Linux Ubuntu Add A User

If you prefer, you can also download your preferred distro(s) via the command line:

Download using PowerShell

To download distros using PowerShell, use the Invoke-WebRequest cmdlet. Here's a sample instruction to download Ubuntu 16.04.

Tip

If the download is taking a long time, turn off the progress bar by setting $ProgressPreference = 'SilentlyContinue'

Download using curl

Windows 10 Spring 2018 Update (or later) includes the popular curl command-line utility with which you can invoke web requests (i.e. HTTP GET, POST, PUT, etc. commands) from the command line. You can use curl.exe to download the above distros:

In the above example, curl.exe is executed (not just curl) to ensure that, in PowerShell, the real curl executable is invoked, not the PowerShell curl alias for Invoke-WebRequest

Note: Using curl might be preferable if you have to invoke/script download steps using Cmd shell and/or .bat / .cmd scripts.

Add A User Manually In Linux

Add A User In Linux

Installing your distro

If you're using Windows 10 you can install your distro with PowerShell. Simply navigate to folder containing the distro downloaded from above, and in that directory run the following command where app_name is the name of your distro .appx file.

If you are using Windows server you can find the install instructions on the Windows Server documentation page.

Once your distro is installed please refer to the Initialization Steps page to initialize your new distro.