ADDUSER(8) System Manager's Manual ADDUSER(8)
NAME
adduser, addgroup - add a user or group to the system
SYNOPSIS
adduser [options] [--home DIR] [--shell SHELL] [--no-create-home]
[--uid ID] [--firstuid ID] [--lastuid ID] [--ingroup GROUP | --gid ID]
[--disabled-password] [--disabled-login] [--gecos GECOS] [--add_ex-
tra_groups] user
adduser --system [options] [--home DIR] [--shell SHELL] [--no-create-
home] [--uid ID] [--group | --ingroup GROUP | --gid ID] [--disabled-
password] [--disabled-login] [--gecos GECOS] user
addgroup [options] [--gid ID] group
addgroup --system [options] [--gid ID] group
adduser [options] user group
COMMON OPTIONS
[--quiet] [--debug] [--force-badname] [--help|-h] [--version] [--conf
FILE]
DESCRIPTION
adduser and addgroup add users and groups to the system according to
command line options and configuration information in /etc/ad-
duser.conf. They are friendlier front ends to the low level tools like
useradd, groupadd and usermod programs, by default choosing Debian pol-
icy conformant UID and GID values, creating a home directory with
skeletal configuration, running a custom script, and other features.
adduser and addgroup can be run in one of five modes:
Add a normal user
If called with one non-option argument and without the --system or
--group options, adduser will add a normal user.
adduser will choose the first available UID from the range specified
for normal users in the configuration file. The UID can be overridden
with the --uid option.
The range specified in the configuration file may be overridden with
the --firstuid and --lastuid options.
By default, each user in Debian GNU/Linux is given a corresponding
group with the same name. Usergroups allow group writable directories
to be easily maintained by placing the appropriate users in the new
group, setting the set-group-ID bit in the directory, and ensuring that
all users use a umask of 002. If this option is turned off by setting
USERGROUPS to no, all users' GIDs are set to USERS_GID. Users' primary
groups can also be overridden from the command line with the --gid or
--ingroup options to set the group by id or name, respectively. Also,
users can be added to one or more groups defined in adduser.conf either
by setting ADD_EXTRA_GROUPS to 1 in adduser.conf, or by passing
--add_extra_groups on the commandline.
adduser will create a home directory subject to DHOME, GROUPHOMES, and
LETTERHOMES. The home directory can be overridden from the command
line with the --home option, and the shell with the --shell option. The
home directory's set-group-ID bit is set if USERGROUPS is yes so that
any files created in the user's home directory will have the correct
group.
adduser will copy files from SKEL into the home directory and prompt
for finger (gecos) information and a password. The gecos may also be
set with the --gecos option. With the --disabled-login option, the ac-
count will be created but will be disabled until a password is set. The
--disabled-password option will not set a password, but login is still
possible (for example with SSH RSA keys).
If the file /usr/local/sbin/adduser.local exists, it will be executed
after the user account has been set up in order to do any local setup.
The arguments passed to adduser.local are:
username uid gid home-directory
The environment variable VERBOSE is set according to the following
rule:
0 if --quiet is specified
1 if neither
--quiet nor --debug is specified
2 if --debug is specified
(The same applies to the variable DEBUG, but DEBUG is deprecated
and will be removed in a later version of adduser.)
Add a system user
If called with one non-option argument and the --system option, adduser
will add a system user. If a user with the same name already exists in
the system uid range (or, if the uid is specified, if a user with that
uid already exists), adduser will exit with a warning. This warning can
be suppressed by adding --quiet.
adduser will choose the first available UID from the range specified
for system users in the configuration file (FIRST_SYSTEM_UID and
LAST_SYSTEM_UID). If you want to have a specific UID, you can specify
it using the --uid option.
By default, system users are placed in the nogroup group. To place the
new system user in an already existing group, use the --gid or --in-
group options. To place the new system user in a new group with the
same ID, use the --group option.
A home directory is created by the same rules as for normal users. The
new system user will have the shell /usr/sbin/nologin (unless overrid-
den with the --shell option), and have logins disabled. Skeletal con-
figuration files are not copied.
Add a user group
If adduser is called with the --group option and without the --system
option, or addgroup is called respectively, a user group will be added.
A GID will be chosen from the range specified for system GIDS in the
configuration file (FIRST_GID, LAST_GID). To override that mechanism
you can give the GID using the --gid option.
The group is created with no users.
Add a system group
If addgroup is called with the --system option, a system group will be
added.
A GID will be chosen from the range specified for system GIDS in the
configuration file (FIRST_SYSTEM_GID, LAST_SYSTEM_GID). To override
that mechanism you can give the GID using the --gid option.
The group is created with no users.
Add an existing user to an existing group
If called with two non-option arguments, adduser will add an existing
user to an existing group.
OPTIONS
--conf FILE
Use FILE instead of /etc/adduser.conf.
--disabled-login
Do not run passwd to set the password. The user won't be able
to use her account until the password is set.
--disabled-password
Like --disabled-login, but logins are still possible (for exam-
ple using SSH RSA keys) but not using password authentication.
--force-badname
By default, user and group names are checked against the config-
urable regular expression NAME_REGEX specified in the configura-
tion file. This option forces adduser and addgroup to apply only
a weak check for validity of the name. NAME_REGEX is described
in adduser.conf(5).
--gecos GECOS
Set the gecos field for the new entry generated. adduser will
not ask for finger information if this option is given.
--gid ID
When creating a group, this option forces the new groupid to be
the given number. When creating a user, this option will put
the user in that group.
--group
When combined with --system, a group with the same name and ID
as the system user is created. If not combined with --system, a
group with the given name is created. This is the default ac-
tion if the program is invoked as addgroup.
--help Display brief instructions.
--home DIR
Use DIR as the user's home directory, rather than the default
specified by the configuration file. If the directory does not
exist, it is created and skeleton files are copied.
--shell SHELL
Use SHELL as the user's login shell, rather than the default
specified by the configuration file.
--ingroup GROUP
Add the new user to GROUP instead of a usergroup or the default
group defined by USERS_GID in the configuration file. This af-
fects the users primary group. To add additional groups, see
the add_extra_groups option.
--no-create-home
Do not create the home directory, even if it doesn't exist.
--quiet
Suppress informational messages, only show warnings and errors.
--debug
Be verbose, most useful if you want to nail down a problem with
adduser.
--system
Create a system user or group.
--uid ID
Force the new userid to be the given number. adduser will fail
if the userid is already taken.
--firstuid ID
Override the first uid in the range that the uid is chosen from
(overrides FIRST_UID specified in the configuration file).
--lastuid ID
Override the last uid in the range that the uid is chosen from (
LAST_UID )
--add_extra_groups
Add new user to extra groups defined in the configuration file.
--version
Display version and copyright information.
EXIT VALUES
0 The user exists as specified. This can have 2 causes: The user
was created by adduser or the user was already present on the
system before adduser was invoked. If adduser was returning 0 ,
invoking adduser a second time with the same parameters as be-
fore also returns 0.
1 Creating the user or group failed because it was already present
with other UID/GID than specified. The username or groupname was
rejected because of a mismatch with the configured regular ex-
pressions, see adduser.conf(5). Adduser has been aborted by a
signal.
Or for many other yet undocumented reasons which are printed to
console then. You may then consider to remove --quiet to make
adduser more verbose.
FILES
/etc/adduser.conf
Default configuration file for adduser and addgroup
/usr/local/sbin/adduser.local
Optional custom add-ons.
SEE ALSO
adduser.conf(5), deluser(8), groupadd(8), useradd(8), usermod(8), De-
bian Policy 9.2.2.
COPYRIGHT
Copyright (C) 1997, 1998, 1999 Guy Maor. Modifications by Roland Bauer-
schmidt and Marc Haber. Additional patches by Joerg Hoh and Stephen
Gran.
Copyright (C) 1995 Ted Hajek, with a great deal borrowed from the orig-
inal Debian adduser
Copyright (C) 1994 Ian Murdock. adduser is free software; see the GNU
General Public Licence version 2 or later for copying conditions.
There is no warranty.
Debian GNU/Linux Version 3.118 ADDUSER(8)