ADDUSER

Section: Maintenance Commands (8)
Updated: Version 3.113+nmu3
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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_extra_groups] user

Section: Maintenance Commands (8)Updated: Version 3.113+nmu3adduser, addgroup – add a user or group to the system   [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_extra_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

[–quiet] [–debug] [–force-badname] [–help|-h] [–version] [–conf FILE]  

adduser and addgroup

add users and groups to the system according to command line options
and configuration information in
/etc/adduser.conf.

They are friendlier front ends to the low level tools like
useradd,
groupadd and usermod

programs, by default choosing Debian policy 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.

If called with one non-option argument and without theoroptions,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 account 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”.

If called with one non-option argument and theoption,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 –ingroup

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
/bin/false

(unless overridden with the
–shell

option), and have logins disabled. Skeletal configuration 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.

Ifis called with theoption and without theoption, oris 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.

Ifis called with theoption, 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 example using
SSH RSA keys) but not using password authentication.

–force-badname

By default, user and group names are checked against the configurable
regular expression
NAME_REGEX

specified in the configuration file. This option forces
adduser

and
addgroup

to apply only a weak check for validity of the name.

–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 action 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 affects 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

If called with two non-option arguments,will add an existing user to an existing group.  

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 before 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 expressions, 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

 

SEE ALSO

 

COPYRIGHT

Copyright (C) 1997, 1998, 1999 Guy Maor. Modifications by Roland
Bauerschmidt and Marc Haber. Additional patches by Joerg Hoh and Stephen Gran.

Copyright (C) 1995 Ted Hajek, with a great deal borrowed from the original
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.

Copyright (C) 1997, 1998, 1999 Guy Maor. Modifications by Roland Bauerschmidt and Marc Haber. Additional patches by Joerg Hoh and Stephen Gran.Copyright (C) 1995 Ted Hajek, with a great deal borrowed from the original DebianCopyright (C) 1994 Ian Murdock.is free software; see the GNU General Public Licence version 2 or later for copying conditions. There iswarranty.

 

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