adduser, addgroup - add or manipulate users or groups
adduser [ --add-extra-groups ] [ --allow-all-names ] [ --allow-bad-names ] [ --comment comment ] [ --conf file ] [ --debug ] [ --disabled-login ] [ --disabled-password ] [ --encrypt-home ] [ --firstgid id ] [ --firstuid id ] [ --gid id ] [ --home dir ] [ --ingroup group ] [ --lastgid id ] [ --lastuid id ] [ --no-create-home ] [ --shell shell ] [ --quiet ] [ --uid id ] [ --verbose ] [ --stdoutmsglevel prio ] [ --stderrmsglevel prio ] [ --logmsglevel prio ] user adduser --system [ --comment comment ] [ --conf file ] [ --debug ] [ --gid id ] [ --group ] [ --home dir ] [ --ingroup group ] [ --no-create-home ] [ --shell shell ] [ --uid id ] [ --quiet ] [ --verbose ] [ --stdoutmsglevel prio ] [ --stderrmsglevel prio ] [ --logmsglevel prio ] user adduser --group [ --conf file ] [ --debug ] [ --firstgid id ] [ --gid ID ] [ --lastgid id ] [ --quiet ] [ --verbose ] [ --stdoutmsglevel prio ] [ --stderrmsglevel prio ] [ --logmsglevel prio ] group addgroup [ --conf file ] [ --debug ] [ --firstgid id ] [ --gid ID ] [ --lastgid id ] [ --quiet ] [ --verbose ] [ --stdoutmsglevel prio ] [ --stderrmsglevel prio ] [ --logmsglevel prio ] group addgroup --system [ --gid id ] [ --conf file ] [ --quiet ] [ --verbose ] [ --stdoutmsglevel prio ] [ --stderrmsglevel prio ] [ --logmsglevel prio ] group adduser [ --conf file ] [ --debug ] [ --quiet ] [ --verbose ] [ --stdoutmsglevel prio ] [ --stderrmsglevel prio ] [ --logmsglevel prio ] user group adduser --help adduser --version
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 are intended as a policy layer, making it easier for package maintainers and local administrators to create local system accounts in the way Debian expects them to be created, taking the burden to adapt to the probably changing specifications of Debian policy. adduser --system takes special attention on just needing a single call in the package maintainer scripts without any conditional wrappers, error suppression or other scaffolding.
adduser honors the distinction between
dynamically allocated system users and groups and
dynamically allocated user accounts that is documented in
Debian Policy, Chapter 9.2.2.
For a full list and explanations of all options, see the OPTIONS section.
adduser and addgroup can be run in one of five modes:
If called with one non-option argument and without the
--system or --group options,
adduser will add a normal user, that means a
dynamically allocated user account in the sense of Debian
Policy. This is commonly referred to in adduser as a
non-system user.
adduser will choose the first available UID from the range specified by FIRST_UID and LAST_UID in the configuration file. The range may be overridden with the --firstuid and --lastuid options. Finally, the UID can be set fully manually with the --uid option.
By default, each user is given a corresponding group with the same
name. This is commonly called Usergroups and allows 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.
For a usergroup, adduser will choose the first available GID from the range specified by FIRST_GID and LAST_GID in the configuration file. The range may be overridden with the --firstgid and --lastgid options. Finally, the GID can be set fully manually with the --gid option.
The interaction between USERS_GID, USERS_GROUP, and USERGROUPS is explained in detail in adduser.conf(5).
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 supplemental groups defined as EXTRA_GROUPS in the configuration file either by setting ADD_EXTRA_GROUPS to 1 in the configuration file, or by passing --add-extra-groups on the command line.
adduser will copy files from /etc/skel into
the home directory and prompt for the comment field and a password if
those functions have not been turned off / overridden from the command
line.
UID, comment, home directory and shell might be pre-determined with the UID_POOL and GID_POOL option, documented in adduser.conf(5).
To set up an encrypted home directory for the new user, add the --encrypt-home option. For more information, refer to the -b option of ecryptfs-setup-private(1).
If called with one non-option argument and the
--system option, adduser will add a
dynamically allocated system user, often abbreviated as
system user in the context of the adduser
package.
adduser will choose the first available UID from the range specified by FIRST_SYSTEM_UID and LAST_SYSTEM_UID in the configuration file. This can be overridden with 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. If the --group is given and the identically named group does not already exist, it is created with the same ID.
If no home directory is specified, the default home directory for a
new system user is /nonexistent. This directory should never
exist on any Debian system, and adduser will never
create it automatically.
Unless a shell is explicitly set with the --shell
option, the new system user will have the shell set to
/usr/sbin/nologin. adduser --system does not
set a password for the new account. Skeletal configuration files are not
copied.
Other options will behave as for the creation of a normal user. The files referenced by UID_POOL and GID_POOL do also work.
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 dynamically allocated system group, often abbreviated as
system group in the context of the adduser
package, will be created if adduser is called with the
--system option.
A GID will be chosen from the respective range specified for GIDs in the configuration file (FIRST_GID, LAST_GID, FIRST_SYSTEM_GID, LAST_SYSTEM_GID). To override that mechanism, you can give the GID using the --gid option.
For non-system groups, the range specified in the configuration file may be overridden with the --firstgid and --lastgid options.
The group is created with no members.
If called with two non-option arguments, adduser will add an existing user to an existing group.
Different modes of adduser allow different options. If no valid modes are listed for a option, it is accepted in all modes.
Short versions for certain options may exist for historical reasons. They are going to stay supported, but are removed from the documentation. Users are advised to migrate to the long version of options.
Add new user to extra groups defined in the configuration files' EXTRA_GROUPS setting. The old spelling --add_extra_groups is deprecated and will be supported in Debian bookworm only. Valid Modes: adduser, adduser --system.
Allow any user- and groupname which is supported by the underlying useradd(8), including names containing non-ASCII characters. See VALID NAMES in adduser.conf(5). Valid Modes: adduser, adduser --system, addgroup, addgroup --system.
Disable NAME_REGEX and SYS_NAME_REGEX check of names. Only a weaker check for validity of the name is applied. See VALID NAMES in adduser.conf(5). Valid Modes: adduser, adduser --system, addgroup, addgroup --system.
comment Set the comment field for the new entry generated. adduser will not ask for the information if this option is given. This field is also known under the name GECOS field and contains information that is used by the finger(1) command. This used to be the --gecos option, which is deprecated and will be removed after Debian bookworm. Valid Modes: adduser, adduser --system.
file Use file instead of /etc/adduser.conf. Multiple
--conf options can be given.
Synonymous to --stdoutmsglevel=debug. Deprecated.
Do not run passwd(1) to set a password. In most
situations, logins are still possible though (for example using SSH keys
or through PAM) for reasons that are beyond adduser's
scope. --disabled-login will additionally set the shell
to /usr/sbin/nologin. Valid Mode: adduser.
ID ID ID ID Override the first UID / last UID / first GID / last GID in the range that the uid is chosen from (FIRST_UID, LAST_UID, FIRST_GID and LAST_GID, FIRST_SYSTEM_UID, LAST_SYSTEM_UID, FIRST_SYSTEM_GID and LAST_SYSTEM_GID in the configuration file). If a group is created as a usergroup, --firstgid and --lastgid are ignored. The group gets the same ID as the user. Valid Modes: adduser, adduser --system, for --firstgid and --lastgid also addgroup.
These are the deprecated forms of --allow-bad-names.
It will be removed during the release cycle of the Debian release after
bookworm.
Uses extra users as the database.
ID When creating a group, this option sets the group ID number of the
new group to GID. When creating a user, this option sets the
primary group ID number of the new user to GID. Valid Modes:
adduser, adduser --system,
addgroup, addgroup --system.
Using this option in adduser --system indicates that the new user should get an identically named group as its primary group. If that identically named group is not already present, it is created. If not combined with --system, a group with the given name is created. The latter is the default action if the program is invoked as addgroup. Valid Modes: adduser --system, addgroup, addgroup --system.
Display brief instructions.
dir Use dir as the user's home directory, rather than the
default specified by the configuration file (or /nonexistent if
adduser --system is used). If the directory does not
exist, it is created. Valid Modes: adduser,
adduser --system.
GROUP When creating a user, this option sets the primary group ID number of the new user to the GID of the named group. Unlike with the --gid option, the group is specified here by name rather than by numeric ID number. The group must already exist. Valid Modes: adduser, adduser --system.
ID ID Override the last UID / last GID. See --firstuid.
Do not create a home directory for the new user. Note that the
pathname for the new user's home directory will still be entered in the
appropriate field in the /etc/passwd file. The use of this
option does not imply that this field should be empty. Rather, it
indicates to adduser that some other mechanism will be
responsible for initializing the new user's home directory. Valid Modes:
adduser, adduser --system.
Synonymous to --stdoutmsglevel=warn. Deprecated.
shell Use shell as the user's login shell, rather than the default
specified by the configuration file (or /usr/sbin/nologin if
adduser --system is used). Valid Modes:
adduser, adduser --system.
Nomally, adduser creates dynamically allocated
user accounts and groups as defined in Debian Policy, Chapter
9.2.2. With this option, adduser creates a
dynamically allocated system user and group and changes its
mode respectively. Valid Modes: adduser,
addgroup.
ID Force the new userid to be the given number. adduser will fail if the userid is already taken. Valid Modes: adduser, adduser --system.
Synonymous to --stdoutmsglevel=info. Deprecated.
prio prio prio Minimum priority for messages logged to syslog/journal and the
console, respectively. Values are trace, debug,
info, warn, err, and fatal. Messages
with the priority set here or higher get printed to the respective
medium. Messages printed to stderr are not repeated on stdout. That
allows the local admin to control adduser's chattiness
on the console and in the log independently, keeping probably confusing
information to itself while still leaving helpful information in the
log.
Display version and copyright information.
Success: The user or group exists as specified. This can have 2 causes: The user or group was created by this call to adduser or the user or group was already present on the system as specified before adduser was invoked. If adduser --system is invoked for a user already existing with the requested or compatible attributes, it will also return 0.
The object that adduser was asked to create does already exist.
The object that adduser or deluser was asked to operate on does not exist.
The object that adduser or deluser was asked to operate on does ont have the properties that are required to complete the operation: A user (a group) that was requested to be created as a system user (group) does already exist and is not a system user (group), or A user (group) that was requested to be created with a certain UID (GID) does already exist and has a different UID (GID), or A system user (group) that was requested to be deleted does exist, but is not a system user (group).
The UID (GID) that was explicitly requested for a new user (group) is already in use.
There is no available UID (GID) in the requested range.
There is no group with the requested GID for the primary group for a new user.
The chosen name for a new user or a new group does not conform to the selected naming rules.
The home directory of a new user must be an absolute path.
The group that was requested to be deleted is not empty.
The user that was requested to be removed from a group is not a member in the first place.
It is not possible to remove a user from its primary group, or no primary group selected for a new user by any method.
Incorrect number or order of command line parameters detected.
Incompatible options set in configuration file.
Mutually incompatible command line options detected.
adduser and deluser invoked as non-root and thus cannot work.
deluser will refuse to delete the root
account.
A function was requested that needs more packages to be installed. See Recommends: and Suggests: of the adduser package.
Adduser was aborted for some reason and tried to roll back the changes that were done during execution.
Internal adduser error. This should not happen. Please try to reproduce the issue and file a bug report.
Error creating and handling the lock.
Error accessing the configuration file(s).
Error accessing a pool file.
Error reading a pool file, syntax error in file.
Error accessing auxiliary files.
An executable that is needed by adduser or deluser cannot be found. Check your installation and dependencies.
Executing an external command returned some unexpected error.
An external command was terminated with a signal.
A syscall terminated with unexpected error.
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.
adduser needs root privileges and offers, via the --conf command line option to use different configuration files. Do not use sudo(8) or similar tools to give partial privileges to adduser with restricted command line parameters. This is easy to circumvent and might allow users to create arbitrary accounts. If you want this, consider writing your own wrapper script and giving privileges to execute that script.
/etc/adduser.conf/usr/local/sbin/adduser.localOptional custom add-ons, see adduser.local(8)
Unfortunately, the term system account suffers from double
use in Debian. It both means an account for the actual Debian system,
distinguishing itself from an application account which might
exist in the user database of some application running on Debian. A
system account in this definition has the potential to log in
to the actual system, has a UID, can be member in system groups, can own
files and processes. Debian Policy, au contraire, in its Chapter 9.2.2,
makes a distinguishment of dynamically allocated system users and
groups and dynamically allocated user accounts, meaning in
both cases special instances of system accounts. Care must be
taken to not confuse this terminology. Since adduser
and deluser(8) never address application
accounts and everything in this package concerns system
accounts here, the usage of the terms user account and
system account is actually not ambiguous in the context of this
package. For clarity, this document uses the definition local system
account or group if the distinction to application
accounts or accounts managed in a directory service is needed.
adduser used to have the vision to be the universal front end to the various directory services for creation and deletion of regular and system accounts in Debian since the 1990ies. This vision has been abandoned as of 2022. The rationale behind this includes: that in practice, a small server system is not going to have write access to an enterprise-wide directory service anyway, that locally installed packages are hard to manage with centrally controlled system accounts, that enterprise directory services have their own management processes anyway and that the personpower of the adduser team is unlikely to be ever strong enough to write and maintain support for the plethora of directory services that need support.
adduser will constrict itself to being a policy layer for the management of local system accounts, using the tools from the password package for the actual work.
Inconsistent use of terminology around the term system account in docs and code is a bug. Please report this and allow us to improve our docs.
adduser takes special attention to be directly usable in Debian maintainer scripts without conditional wrappers, error suppression and other scaffolding. The only thing that the package maintainer should need to code is a check for the presence of the executable in the postrm script. The adduser maintainers consider the need for additional scaffolding a bug and encourage their fellow Debian package maintainers to file bugs against the adduser package in this case.
adduser.conf(5), deluser(8), groupadd(8), useradd(8), usermod(8), Debian Policy 9.2.2.