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:
This is the name of the user.
It can be the name of a new user or the name of an existing user
(or an 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.
This field will be encrypted and used as the new value of the
This field is used to define the UID of the user.
If the field is empty, an new (unused) UID will be defined
automatically by newusers.
If this field contains a number, this number will be used as the
If this field contains the name of an existing user (or the name of
an 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.
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
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.
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.
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
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:
Display help message and exit.
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
-R, --root CHROOT_DIR
Apply changes in the CHROOT_DIR directory and use the configuration
files from the CHROOT_DIR directory.
The input file must be protected since it contains unencrypted
The following configuration variables in /etc/login.defs change the
behavior of this tool:
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.
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).
The 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).
The 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
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
SYS_UID_MAX (number), SYS_UID_MIN (number)
Range of user IDs used for the creation of system users by useradd
The default value for SYS_UID_MIN (resp. SYS_UID_MAX) is 101
UID_MAX (number), UID_MIN (number)
Range of user IDs used for the creation of regular users by useradd
The default value for UID_MIN (resp. UID_MAX) is 1000 (resp.
The file mode creation mask is initialized to this value. If not
specified, the mask will be initialized to 022.
Group account information.
Secure group account information.
Shadow password suite configuration.
PAM configuration for newusers.
login.defs(5), passwd(1), useradd(8).
shadow-utils 22.214.171.124 05/16/2017 NEWUSERS(8)
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