groupadd(8) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | CONFIGURATION | FILES | CAVEATS | EXIT VALUES | SEE ALSO | COLOPHON

GROUPADD(8)            System Management Commands            GROUPADD(8)

NAME         top

       groupadd - create a new group

SYNOPSIS         top


       groupadd [OPTIONS] NEWGROUP

DESCRIPTION         top

       The groupadd command creates a new group account using the values
       specified on the command line plus the default values from the
       system. The new group will be entered into the system files as
       needed.

       Groupnames may contain only lower and upper case letters, digits,
       underscores, or dashes. They can end with a dollar sign. Dashes
       are not allowed at the beginning of the groupname. Fully numeric
       groupnames and groupnames . or .. are also disallowed.

       Groupnames may only be up to 32 characters long.

OPTIONS         top

       The options which apply to the groupadd command are:

       -f, --force
           This option causes the command to simply exit with success
           status if the specified group already exists. When used with
           -g, and the specified GID already exists, another (unique)
           GID is chosen (i.e.  -g is turned off).

       -g, --gid GID
           The numerical value of the group's ID.  GID must be unique,
           unless the -o option is used. The value must be non-negative.
           The default is to use the smallest ID value greater than or
           equal to GID_MIN and greater than every other group.

           See also the -r option and the GID_MAX description.

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

       -K, --key KEY=VALUE
           Overrides /etc/login.defs defaults (GID_MIN, GID_MAX and
           others). Multiple -K options can be specified.

           Example: -K GID_MIN=100  -K GID_MAX=499

           Note: -K GID_MIN=10,GID_MAX=499 doesn't work yet.

       -o, --non-unique
           permits the creation of a group with an already used
           numerical ID. As a result, for this GID, the mapping towards
           group NEWGROUP may not be unique.

       -p, --password PASSWORD
           defines an initial password for the group account. PASSWORD
           is expected to be encrypted, as returned by crypt (3).

           Without this option, the group account will be locked and
           with no password defined, i.e. a single exclamation mark in
           the respective field of ths system account file /etc/group or
           /etc/gshadow.

           Note: This option is not recommended because the password (or
           encrypted password) will be visible by users listing the
           processes.

           You should make sure the password respects the system's
           password policy.

       -r, --system
           Create a system group.

           The numeric identifiers of new system groups are chosen in
           the SYS_GID_MIN-SYS_GID_MAX range, defined in login.defs,
           instead of GID_MIN-GID_MAX.

       -R, --root CHROOT_DIR
           Apply changes in the CHROOT_DIR directory and use the
           configuration files from the CHROOT_DIR directory. Only
           absolute paths are supported.

       -P, --prefix PREFIX_DIR
           Apply changes to configuration files under the root
           filesystem found under the directory PREFIX_DIR. This option
           does not chroot and is intended for preparing a
           cross-compilation target. Some limitations: NIS and LDAP
           users/groups are not verified. PAM authentication is using
           the host files. No SELINUX support.

       -U, --users
           A list of usernames to add as members of the group.

           The default behavior (if the -g, -N, and -U options are not
           specified) is defined by the USERGROUPS_ENAB variable in
           /etc/login.defs.

CONFIGURATION         top

       The following configuration variables in /etc/login.defs change
       the behavior of this tool:

       GID_MAX (number), GID_MIN (number)
           Range of group IDs used for the creation of regular groups by
           useradd, groupadd, or newusers.

           The default value for GID_MIN (resp.  GID_MAX) is 1000 (resp.
           60000).

       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.

       SYS_GID_MAX (number), SYS_GID_MIN (number)
           Range of group IDs used for the creation of system groups by
           useradd, groupadd, or newusers.

           The default value for SYS_GID_MIN (resp.  SYS_GID_MAX) is 101
           (resp.  GID_MIN-1).

FILES         top

       /etc/group
           Group account information.

       /etc/gshadow
           Secure group account information.

       /etc/login.defs
           Shadow password suite configuration.

CAVEATS         top

       You may not add a NIS or LDAP group. This must be performed on
       the corresponding server.

       If the groupname already exists in an external group database
       such as NIS or LDAP, groupadd will deny the group creation
       request.

EXIT VALUES         top

       The groupadd command exits with the following values:

       0
           success

       2
           invalid command syntax

       3
           invalid argument to option

       4
           GID is already used (when called without -o)

       9
           group name is already used

       10
           can't update group file

SEE ALSO         top

       chfn(1), chsh(1), passwd(1), gpasswd(8), groupdel(8),
       groupmod(8), login.defs(5), useradd(8), userdel(8), usermod(8).

COLOPHON         top

       This page is part of the shadow-utils (utilities for managing
       accounts and shadow password files) project.  Information about
       the project can be found at 
       ⟨https://github.com/shadow-maint/shadow⟩.  If you have a bug
       report for this manual page, send it to
       [email protected].  This page was obtained
       from the project's upstream Git repository
       ⟨https://github.com/shadow-maint/shadow⟩ on 2024-06-15.  (At that
       time, the date of the most recent commit that was found in the
       repository was 2024-06-13.)  If you discover any rendering
       problems in this HTML version of the page, or you believe there
       is a better or more up-to-date source for the page, or you have
       corrections or improvements to the information in this COLOPHON
       (which is not part of the original manual page), send a mail to
       [email protected]

shadow-utils 4.14.0            06/15/2024                    GROUPADD(8)

Pages that refer to this page: gpasswd(1)homectl(1)chgpasswd(8)groupdel(8)groupmems(8)groupmod(8)useradd(8)userdel(8)usermod(8)