Manual: newusers

NEWUSERS(8)				 System Management Commands				 NEWUSERS(8)

NAME
       newusers - update and create new users in batch

SYNOPSIS

       newusers [options] [file]

DESCRIPTION
       The newusers command reads a file (or the standard input by default) and uses this information to
       update a set of existing users or to create new users. Each line is in the same format as the
       standard password file (see passwd(5)) with the exceptions explained below:

       pw_name:pw_passwd:pw_uid:pw_gid:pw_gecos:pw_dir:pw_shell

       pw_name
	   This is the name of the user.

	   It can be the name of a new user or the name of an existing user (or a user created before by
	   newusers). In case of an existing user, the user's information will be changed, otherwise a new
	   user will be created.

       pw_passwd
	   This field will be encrypted and used as the new value of the encrypted password.

       pw_uid
	   This field is used to define the UID of the user.

	   If the field is empty, a new (unused) UID will be defined automatically by newusers.

	   If this field contains a number, this number will be used as the UID.

	   If this field contains the name of an existing user (or the name of a user created before by
	   newusers), the UID of the specified user will be used.

	   If the UID of an existing user is changed, the files ownership of the user's file should be fixed
	   manually.

       pw_gid
	   This field is used to define the primary group ID for the user.

	   If this field contains the name of an existing group (or a group created before by newusers), the
	   GID of this group will be used as the primary group ID for the user.

	   If this field is a number, this number will be used as the primary group ID of the user. If no
	   groups exist with this GID, a new group will be created with this GID, and the name of the user.

	   If this field is empty, a new group will be created with the name of the user and a GID will be
	   automatically defined by newusers to be used as the primary group ID for the user and as the GID
	   for the new group.

	   If this field contains the name of a group which does not exist (and was not created before by
	   newusers), a new group will be created with the specified name and a GID will be automatically
	   defined by newusers to be used as the primary group ID for the user and GID for the new group.

       pw_gecos
	   This field is copied in the GECOS field of the user.

       pw_dir
	   This field is used to define the home directory of the user.

	   If this field does not specify an existing directory, the specified directory is created, with
	   ownership set to the user being created or updated and its primary group. Note that newusers does
	   not create parent directories of the new user's home directory. The newusers command will fail to
	   create the home directory if the parent directories do not exist, and will send a message to
	   stderr informing the user of the failure. The newusers command will not halt or return a failure
	   to the calling shell if it fails to create the home directory, it will continue to process the
	   batch of new users specified.

	   If the home directory of an existing user is changed, newusers does not move or copy the content
	   of the old directory to the new location. This should be done manually.

       pw_shell
	   This field defines the shell of the user. No checks are performed on this field.

       newusers first tries to create or change all the specified users, and then write these changes to the
       user or group databases. If an error occurs (except in the final writes to the databases), no changes
       are committed to the databases.

       During this first pass, users are created with a locked password (and passwords are not changed for
       the users which are not created). A second pass is used to update the passwords using PAM. Failures
       to update a password are reported, but will not stop the other password updates.

       This command is intended to be used in a large system environment where many accounts are updated at
       a single time.

OPTIONS
       The options which apply to the newusers command are:

       --badname
	   Allow names that do not conform to standards.

       -h, --help
	   Display help message and exit.

       -r, --system
	   Create 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 login.defs, instead of
	   UID_MIN-UID_MAX (and their GID counterparts for the creation of groups).

       -R, --root CHROOT_DIR
	   Apply changes in the CHROOT_DIR directory and use the configuration files from the CHROOT_DIR
	   directory. Only absolute paths are supported.

CAVEATS
       The input file must be protected since it contains unencrypted passwords.

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

       GID_MAX (number), GID_MIN (number)
	   Range of group IDs used for the creation of regular groups by useradd, groupadd, or newusers.

	   The default value for GID_MIN (resp.	 GID_MAX) is 1000 (resp. 60000).

       HOME_MODE (number)
	   The mode for new home directories. If not specified, the UMASK is used to create the mode.

	   useradd and newusers use this to set the mode of the home directory they create.

       MAX_MEMBERS_PER_GROUP (number)
	   Maximum 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 GID).

	   The default value is 0, meaning that there are no limits in the number of members in a group.

	   This feature (split group) permits 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 in the Shadow toolsuite). You should
	   not use this variable unless you really need it.

       PASS_MAX_DAYS (number)
	   The 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_DAYS (number)
	   The minimum number of days allowed between password changes. Any password changes attempted
	   sooner than this will be rejected. If not specified, 0 will be assumed (which disables the
	   restriction).

       PASS_WARN_AGE (number)
	   The number of days warning given before a password expires. A zero means warning is given only
	   upon the day of expiration, a value of -1 means no warning is given. If not specified, no warning
	   will be provided.

       SUB_GID_MIN (number), SUB_GID_MAX (number), SUB_GID_COUNT (number)
	   If /etc/subuid exists, the commands useradd and newusers (unless the user already have
	   subordinate group IDs) allocate SUB_GID_COUNT unused group IDs from the range SUB_GID_MIN to
	   SUB_GID_MAX for each new user.

	   The default values for SUB_GID_MIN, SUB_GID_MAX, SUB_GID_COUNT are respectively 100000, 600100000
	   and 65536.

       SUB_UID_MIN (number), SUB_UID_MAX (number), SUB_UID_COUNT (number)
	   If /etc/subuid exists, the commands useradd and newusers (unless the user already have
	   subordinate user IDs) allocate SUB_UID_COUNT unused user IDs from the range SUB_UID_MIN to
	   SUB_UID_MAX for each new user.

	   The default values for SUB_UID_MIN, SUB_UID_MAX, SUB_UID_COUNT are respectively 100000, 600100000
	   and 65536.

       SYS_GID_MAX (number), SYS_GID_MIN (number)
	   Range of group IDs used for the creation of system groups by useradd, groupadd, or newusers.

	   The default value for SYS_GID_MIN (resp.  SYS_GID_MAX) is 101 (resp.	 GID_MIN-1).

       SYS_UID_MAX (number), SYS_UID_MIN (number)
	   Range of user IDs used for the creation of system users by useradd or newusers.

	   The default value for SYS_UID_MIN (resp.  SYS_UID_MAX) is 101 (resp.	 UID_MIN-1).

       UID_MAX (number), UID_MIN (number)
	   Range 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).

       UMASK (number)
	   The 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 if HOME_MODE
	   is not set.

	   It is also used by pam_umask as the default umask value.

FILES
       /etc/passwd
	   User account information.

       /etc/shadow
	   Secure user account information.

       /etc/group
	   Group account information.

       /etc/gshadow
	   Secure group account information.

       /etc/login.defs
	   Shadow password suite configuration.

       /etc/pam.d/newusers
	   PAM configuration for newusers.

       /etc/subgid
	   Per user subordinate group IDs.

       /etc/subuid
	   Per user subordinate user IDs.

SEE ALSO
       login.defs(5), passwd(1), subgid(5), subuid(5), useradd(8).

shadow-utils 4.17.4				 02/02/2026					 NEWUSERS(8)