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USERADD(8)		  System Management Commands		    USERADD(8)



NAME
       useradd - create a new user or update default new user information

SYNOPSIS
       useradd [options] LOGIN

       useradd -D

       useradd -D [options]

DESCRIPTION
       When invoked without the -D option, the useradd command creates a new
       user account using the values specified on the command line and the
       default values from the system. Depending on command line options, the
       useradd command will update system files and may also create the new
       user's home directory and copy initial files. The version provided with
       Red Hat Linux will create a group for each user added to the system by
       default.

OPTIONS
       The options which apply to the useradd command are:

       -c, --comment COMMENT
	  Any text string. It is generally a short description of the login,
	  and is currently used as the field for the user's full name.

       -b, --base-dir BASE_DIR
	  The default base directory for the system if -d dir is not
	  specified.  BASE_DIR is concatenated with the account name to define
	  the home directory. If the -m option is not used, BASE_DIR must
	  exist.

       -d, --home HOME_DIR
	  The new user will be created using HOME_DIR as the value for the
	  user's login directory. The default is to append the LOGIN name to
	  BASE_DIR and use that as the login directory name. The directory
	  HOME_DIR does not have to exist but will not be created if it is
	  missing.

       -e, --expiredate EXPIRE_DATE
	  The date on which the user account will be disabled. The date is
	  specified in the format YYYY-MM-DD.

       -f, --inactive INACTIVE
	  The number of days after a password expires until the account is
	  permanently disabled. A value of 0 disables the account as soon as
	  the password has expired, and a value of -1 disables the feature.
	  The default value is -1.

       -g, --gid GROUP
	  The group name or number of the user's initial login group. The
	  group name must exist. A group number must refer to an already
	  existing group.  /etc/default/useradd.

       -G, --groups GROUP1[,GROUP2,...[,GROUPN]]]
	  A list of supplementary groups which the user is also a member of.
	  Each group is separated from the next by a comma, with no
	  intervening whitespace. The groups are subject to the same
	  restrictions as the group given with the -g option. The default is
	  for the user to belong only to the initial group.

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

       -M The user's home directory will not be created, even if the system
	  wide settings from /etc/login.defs is to create home dirs.

       -m, --create-home
	  The user's home directory will be created if it does not exist. The
	  files contained in SKEL_DIR will be copied to the home directory if
	  the -k option is used, otherwise the files contained in /etc/skel
	  will be used instead. Any directories contained in SKEL_DIR or
	  /etc/skel will be created in the user's home directory as well. The
	  -k option is only valid in conjunction with the -m option. The
	  default is to not create the directory and to not copy any files.

       -l Do not add the user to the last login log file. This is an option
	  added by Red Hat.

       -n A group having the same name as the user being added to the system
	  will be created by default. This option will turn off this Red Hat
	  Linux specific behavior. When this option is used, users by default
	  will be placed in whatever group is specified in
	  /etc/default/useradd. If no default group is defined, group 1 will
	  be used.

       -K, --key KEY=VALUE
	  Overrides /etc/login.defs defaults (UID_MIN, UID_MAX, UMASK,
	  PASS_MAX_DAYS and others).

	  Example: -K PASS_MAX_DAYS=-1 can be used when creating system
	  account to turn off password ageing, even though system account has
	  no password at all. Multiple -K options can be specified, e.g.: -K
	  UID_MIN=100
	   -K UID_MAX=499

	  Note: -K UID_MIN=10,UID_MAX=499 doesn't work yet.

       -o, --non-unique
	  Allow the creation of a user account with a duplicate (non-unique)
	  UID.

       -p, --password PASSWORD
	  The encrypted password, as returned by crypt(3). The default is to
	  disable the account.

       -r This flag is used to create a system account. That is, a user with a
	  UID lower than the value of UID_MIN defined in /etc/login.defs and
	  whose password does not expire. Note that useradd will not create a
	  home directory for such an user, regardless of the default setting
	  in /etc/login.defs. You have to specify -m option if you want a home
	  directory for a system account to be created. This is an option
	  added by Red Hat

       -s, --shell SHELL
	  The name of the user's login shell. The default is to leave this
	  field blank, which causes the system to select the default login
	  shell.

       -u, --uid UID
	  The numerical value of the user's ID. This value must be unique,
	  unless the -o option is used. The value must be non-negative. The
	  default is to use ID value equal to or greater than UID_MIN and
	  smaller then UID_MAX. Values between 0 and UID_MIN are typically
	  reserved for system accounts.

       -Z, --selinux-user SEUSER
	  The SELinux user for the user's login. The default is to leave this
	  field blank, which causes the system to select the default SELinux
	  user.

   Changing the default values
       When invoked with the -D option, useradd will either display the
       current default values, or update the default values from the command
       line. The valid options are

       -b HOME_DIR
	  The initial path prefix for a new user's home directory. The user's
	  name will be affixed to the end of HOME_DIR to create the new
	  directory name if the -d option is not used when creating a new
	  account.

       -e EXPIRE_DATE
	  The date on which the user account is disabled.

       -f INACTIVE
	  The number of days after a password has expired before the account
	  will be disabled.

       -g, --gid GROUP
	  The group name or ID for a new user's initial group. The named group
	  must exist, and a numerical group ID must have an existing entry.

       -s, --shell SHELL
	  The name of the new user's login shell. The named program will be
	  used for all future new user accounts.

       If no options are specified, useradd displays the current default
       values.

NOTES
       The system administrator is responsible for placing the default user
       files in the /etc/skel/ directory.
       This version of useradd was modified by Red Hat to suit Red Hat
       user/group conventions.

CAVEATS
       You may not add a user to a NIS group. This must be performed on the
       NIS server.

       Similarly, if the username already exists in an external user database
       such as NIS, useradd will deny the user account creation request.

FILES
       /etc/passwd
	  User account information.

       /etc/shadow
	  Secure user account information.

       /etc/group
	  Group account information.

       /etc/gshadow
	  Secure group account information.

       /etc/default/useradd
	  Default values for account creation.

       /etc/skel/
	  Directory containing default files.

       /etc/login.defs
	  Shadow password suite configuration.

EXIT VALUES
       The useradd command exits with the following values:

       0  success

       1  can't update password file

       2  invalid command syntax

       3  invalid argument to option

       4  UID already in use (and no -o)

       6  specified group doesn't exist

       9  username already in use

       10 can't update group file

       12 can't create home directory

       13 can't create mail spool

SEE ALSO
       chfn(1), chsh(1), passwd(1), crypt(3), groupadd(8), groupdel(8),
       groupmod(8), login.defs(5), userdel(8), usermod(8).



System Management Commands	  06/24/2006			    USERADD(8)
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