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NAME | SYNOPSIS | DESCRIPTION | OPTIONS | CAVEATS | CONFIGURATION | FILES | SEE ALSO | COLOPHON |
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NEWUSERS(8) System Management Commands NEWUSERS(8)
newusers - update and create new users in batch
newusers [options] [file]
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.
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.
The input file must be protected since it contains unencrypted
passwords.
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.
/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.
login.defs(5), passwd(1), subgid(5), subuid(5), useradd(8).
This page is part of the shadow-utils (utilities for managing
accounts and shadow password files) project. Information about
the project can be found at
⟨https://github.com/shadow-maint/shadow⟩. If you have a bug report
for this manual page, send it to
[email protected]. This page was obtained
from the project's upstream Git repository
⟨https://github.com/shadow-maint/shadow⟩ on 2025-08-11. (At that
time, the date of the most recent commit that was found in the
repository was 2025-08-10.) If you discover any rendering
problems in this HTML version of the page, or you believe there is
a better or more up-to-date source for the page, or you have
corrections or improvements to the information in this COLOPHON
(which is not part of the original manual page), send a mail to
[email protected]
shadow-utils 4.18.0 08/11/2025 NEWUSERS(8)
Pages that refer to this page: newgidmap(1), newuidmap(1), subgid(5), subuid(5), chpasswd(8), useradd(8)
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HTML rendering created 2025-09-06 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
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