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NEWUSERS(8)		  System Management Commands		   NEWUSERS(8)



NAME
       newusers - update and create new users in batch

SYNOPSIS
       newusers [options new_users]

DESCRIPTION
       The newusers command reads a file of user name and clear-text password
       pairs and uses this information to update a group 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
	   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 earlier wbefore 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 Gs the ID 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.

       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 choosen 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).

       -s, --sha-rounds
	   Use the specified number of rounds to encrypt the passwords.

	   The value 0 means that the system will choose the default number of
	   rounds for the crypt method (5000).

	   A minimal value of 1000 and a maximal value of 999,999,999 will be
	   enforced.

	   You can only use this option with the SHA256 or SHA512 crypt
	   method.

	   By default, the number of rounds is defined by the
	   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:

	   o   DES (default)

	   o   MD5

	   o   SHA256

	   o   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.

	   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 of FreeBSD. It supports passwords of unlimited length
	       and longer salt strings. Set to no if you need to copy
	       encrypted passwords to other systems which don't understand the
	       new algorithm. Default is no.

	       This variable is superceded by the ENCRYPT_METHOD variable or
	       by any command line option used to configure the encryption
	       algorithm.

	       This variable is deprecated. You should use ENCRYPT_METHOD.

	   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, -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 1000-999999999 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.

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

	   UID_MAX (number), UID_MIN (number)
	       Range of user IDs used for the creation of regular users by
	       useradd or newusers.

	   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

	       It is also used by login to define users' initial umask. Note
	       that this mask can be overriden by the user's GECOS line (if
	       QUOTAS_ENAB is set) or by the specification of a limit with the
	       K identifier in limits(5).

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.

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



System Management Commands	  07/24/2009			   NEWUSERS(8)