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newusers


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 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.

       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, an 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
           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.

       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

           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.

       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:

       -c, --crypt-method
           Use the specified method to encrypt the passwords.

           The available methods are DES, MD5, NONE, and SHA256 or SHA512 if
           your libc support these methods.

       -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.
           SHA_CRYPT_MIN_ROUNDS and SHA_CRYPT_MAX_ROUNDS variables in
           /etc/login.defs.


CAVEATS

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

       You should make sure the passwords and the encryption method respect
       the system's password policy.


CONFIGURATION

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

       ENCRYPT_METHOD (string)
           This defines the system default encryption algorithm for encrypting
           passwords (if no algorithm are specified on the command line).

           It can take one of these values: DES (default), MD5, SHA256,
           SHA512.

           Note: this parameter overrides the MD5_CRYPT_ENAB variable.

       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).

       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.

       MD5_CRYPT_ENAB (boolean)
           Indicate if passwords must be encrypted using the MD5-based
           algorithm. If set to yes, new passwords will be encrypted using the
           MD5-based algorithm compatible with the one used by recent releases

       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, -1 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 negative
           value means no warning is given. If not specified, no warning will
           be provided.

       SHA_CRYPT_MIN_ROUNDS (number), SHA_CRYPT_MAX_ROUNDS (number)
           When ENCRYPT_METHOD is set to SHA256 or SHA512, this defines the
           number of SHA rounds used by the encryption algorithm by default
           (when the number of rounds is not specified on the command line).

           With a lot of rounds, it is more difficult to brute forcing the
           password. But note also that more CPU resources will be needed to
           authenticate users.

           If not specified, the libc will choose the default number of rounds
           (5000).

           The values must be inside the 1000-999,999,999 range.

           If only one of the SHA_CRYPT_MIN_ROUNDS or SHA_CRYPT_MAX_ROUNDS
           values is set, then this value will be used.

           If SHA_CRYPT_MIN_ROUNDS > SHA_CRYPT_MAX_ROUNDS, the highest value
           will be used.

       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).

       /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.


SEE ALSO

       login.defs(5), passwd(1), useradd(8).


shadow-utils 4.1.5.1 11/05/2016 NEWUSERS(8)



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