path: root/man/man8/groupadd.8

'\" t
.\"     Title: groupadd
.\"    Author: Julianne Frances Haugh
.\" Generator: DocBook XSL Stylesheets vsnapshot <http://docbook.sf.net/>
.\"      Date: 06/21/2024
.\"    Manual: System Management Commands
.\"    Source: shadow-utils 4.15.2
.\"  Language: English
.\"
.TH "GROUPADD" "8" "06/21/2024" "shadow\-utils 4\&.15\&.2" "System Management Commands"
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.SH "NAME"
groupadd \- create a new group
.SH "SYNOPSIS"
.HP \w'\fBgroupadd\fR\ 'u
\fBgroupadd\fR [\fIOPTIONS\fR] \fINEWGROUP\fR
.SH "DESCRIPTION"
.PP
The
\fBgroupadd\fR
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\&.
.PP
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\&.
.PP
Groupnames may only be up to 32 characters long\&.
.SH "OPTIONS"
.PP
The options which apply to the
\fBgroupadd\fR
command are:
.PP
\fB\-f\fR, \fB\-\-force\fR
.RS 4
This option causes the command to simply exit with success status if the specified group already exists\&. When used with
\fB\-g\fR, and the specified GID already exists, another (unique) GID is chosen (i\&.e\&.
\fB\-g\fR
is turned off)\&.
.RE
.PP
\fB\-g\fR, \fB\-\-gid\fR\ \&\fIGID\fR
.RS 4
The numerical value of the group\*(Aqs ID\&.
\fIGID\fR
must be unique, unless the
\fB\-o\fR
option is used\&. The value must be non\-negative\&. The default is to use the smallest ID value greater than or equal to
\fBGID_MIN\fR
and greater than every other group\&.
.sp
See also the
\fB\-r\fR
option and the
\fBGID_MAX\fR
description\&.
.RE
.PP
\fB\-h\fR, \fB\-\-help\fR
.RS 4
Display help message and exit\&.
.RE
.PP
\fB\-K\fR, \fB\-\-key\fR\ \&\fIKEY\fR=\fIVALUE\fR
.RS 4
Overrides
/etc/login\&.defs
defaults (GID_MIN, GID_MAX and others)\&. Multiple
\fB\-K\fR
options can be specified\&.
.sp
Example:
\fB\-K\fR\ \&\fIGID_MIN\fR=\fI100\fR\ \&
\fB\-K\fR\ \&\fIGID_MAX\fR=\fI499\fR
.sp
Note:
\fB\-K\fR\ \&\fIGID_MIN\fR=\fI10\fR,\fIGID_MAX\fR=\fI499\fR
doesn\*(Aqt work yet\&.
.RE
.PP
\fB\-o\fR, \fB\-\-non\-unique\fR
.RS 4
permits the creation of a group with an already used numerical ID\&. As a result, for this
\fIGID\fR, the mapping towards group
\fINEWGROUP\fR
may not be unique\&.
.RE
.PP
\fB\-p\fR, \fB\-\-password\fR\ \&\fIPASSWORD\fR
.RS 4
defines an initial password for the group account\&. PASSWORD is expected to be encrypted, as returned by
\fBcrypt \fR(3)\&.
.sp
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\&.
.sp
\fBNote:\fR
This option is not recommended because the password (or encrypted password) will be visible by users listing the processes\&.
.sp
You should make sure the password respects the system\*(Aqs password policy\&.
.RE
.PP
\fB\-r\fR, \fB\-\-system\fR
.RS 4
Create a system group\&.
.sp
The numeric identifiers of new system groups are chosen in the
\fBSYS_GID_MIN\fR\-\fBSYS_GID_MAX\fR
range, defined in
login\&.defs, instead of
\fBGID_MIN\fR\-\fBGID_MAX\fR\&.
.RE
.PP
\fB\-R\fR, \fB\-\-root\fR\ \&\fICHROOT_DIR\fR
.RS 4
Apply changes in the
\fICHROOT_DIR\fR
directory and use the configuration files from the
\fICHROOT_DIR\fR
directory\&. Only absolute paths are supported\&.
.RE
.PP
\fB\-P\fR, \fB\-\-prefix\fR\ \&\fIPREFIX_DIR\fR
.RS 4
Apply changes to configuration files under the root filesystem found under the directory
\fIPREFIX_DIR\fR\&. 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\&.
.RE
.PP
\fB\-U\fR, \fB\-\-users\fR
.RS 4
A list of usernames to add as members of the group\&.
.sp
The default behavior (if the
\fB\-g\fR,
\fB\-N\fR, and
\fB\-U\fR
options are not specified) is defined by the
\fBUSERGROUPS_ENAB\fR
variable in
/etc/login\&.defs\&.
.RE
.SH "CONFIGURATION"
.PP
The following configuration variables in
/etc/login\&.defs
change the behavior of this tool:
.PP
\fBGID_MAX\fR (number), \fBGID_MIN\fR (number)
.RS 4
Range of group IDs used for the creation of regular groups by
\fBuseradd\fR,
\fBgroupadd\fR, or
\fBnewusers\fR\&.
.sp
The default value for
\fBGID_MIN\fR
(resp\&.
\fBGID_MAX\fR) is 1000 (resp\&. 60000)\&.
.RE
.PP
\fBMAX_MEMBERS_PER_GROUP\fR (number)
.RS 4
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)\&.
.sp
The default value is 0, meaning that there are no limits in the number of members in a group\&.
.sp
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\&.
.sp
If you need to enforce such limit, you can use 25\&.
.sp
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\&.
.RE
.PP
\fBSYS_GID_MAX\fR (number), \fBSYS_GID_MIN\fR (number)
.RS 4
Range of group IDs used for the creation of system groups by
\fBuseradd\fR,
\fBgroupadd\fR, or
\fBnewusers\fR\&.
.sp
The default value for
\fBSYS_GID_MIN\fR
(resp\&.
\fBSYS_GID_MAX\fR) is 101 (resp\&.
\fBGID_MIN\fR\-1)\&.
.RE
.SH "FILES"
.PP
/etc/group
.RS 4
Group account information\&.
.RE
.PP
/etc/gshadow
.RS 4
Secure group account information\&.
.RE
.PP
/etc/login\&.defs
.RS 4
Shadow password suite configuration\&.
.RE
.SH "CAVEATS"
.PP
You may not add a NIS or LDAP group\&. This must be performed on the corresponding server\&.
.PP
If the groupname already exists in an external group database such as NIS or LDAP,
\fBgroupadd\fR
will deny the group creation request\&.
.SH "EXIT VALUES"
.PP
The
\fBgroupadd\fR
command exits with the following values:
.PP
\fI0\fR
.RS 4
success
.RE
.PP
\fI2\fR
.RS 4
invalid command syntax
.RE
.PP
\fI3\fR
.RS 4
invalid argument to option
.RE
.PP
\fI4\fR
.RS 4
GID is already used (when called without
\fB\-o\fR)
.RE
.PP
\fI9\fR
.RS 4
group name is already used
.RE
.PP
\fI10\fR
.RS 4
can\*(Aqt update group file
.RE
.SH "SEE ALSO"
.PP
\fBchfn\fR(1),
\fBchsh\fR(1),
\fBpasswd\fR(1),
\fBgpasswd\fR(8),
\fBgroupdel\fR(8),
\fBgroupmod\fR(8),
\fBlogin.defs\fR(5),
\fBuseradd\fR(8),
\fBuserdel\fR(8),
\fBusermod\fR(8)\&.