groupadd(8)

1GROUPADD(8)               System Management Commands               GROUPADD(8)
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NAME

6       groupadd - create a new group
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SYNOPSIS

9       groupadd [options] group
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DESCRIPTION

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

17       The options which apply to the groupadd command are:
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19       -f, --force
20           This option causes the command to simply exit with success status
21           if the specified group already exists. When used with -g, and the
22           specified GID already exists, another (unique) GID is chosen (i.e.
23           -g is turned off).
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25       -g, --gid GID
26           The numerical value of the group's ID. This value must be unique,
27           unless the -o option is used. The value must be non-negative. The
28           default is to use the smallest ID value greater than or equal to
29           GID_MIN and greater than every other group.
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31           See also the -r option and the GID_MAX description.
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33       -h, --help
34           Display help message and exit.
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36       -K, --key KEY=VALUE
37           Overrides /etc/login.defs defaults (GID_MIN, GID_MAX and others).
38           Multiple -K options can be specified.
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40           Example: -K GID_MIN=100  -K GID_MAX=499
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42           Note: -K GID_MIN=10,GID_MAX=499 doesn't work yet.
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44       -o, --non-unique
45           This option permits to add a group with a non-unique GID.
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47       -p, --password PASSWORD
48           The encrypted password, as returned by crypt(3). The default is to
49           disable the password.
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51           Note: This option is not recommended because the password (or
52           encrypted password) will be visible by users listing the processes.
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54           You should make sure the password respects the system's password
55           policy.
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57       -r, --system
58           Create a system group.
59
60           The numeric identifiers of new system groups are chosen in the
61           SYS_GID_MIN-SYS_GID_MAX range, defined in login.defs, instead of
62           GID_MIN-GID_MAX.
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64       -R, --root CHROOT_DIR
65           Apply changes in the CHROOT_DIR directory and use the configuration
66           files from the CHROOT_DIR directory.
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68       -P, --prefix PREFIX_DIR
69           Apply changes in the PREFIX_DIR directory and use the configuration
70           files from the PREFIX_DIR directory. This option does not chroot
71           and is intended for preparing a cross-compilation target. Some
72           limitations: NIS and LDAP users/groups are not verified. PAM
73           authentication is using the host files. No SELINUX support.
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75       -U, --users
76           A list of usernames to add as members of the group.
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78           The default behavior (if the -g, -N, and -U options are not
79           specified) is defined by the USERGROUPS_ENAB variable in
80           /etc/login.defs.
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CONFIGURATION

83       The following configuration variables in /etc/login.defs change the
84       behavior of this tool:
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86       GID_MAX (number), GID_MIN (number)
87           Range of group IDs used for the creation of regular groups by
88           useradd, groupadd, or newusers.
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90           The default value for GID_MIN (resp.  GID_MAX) is 1000 (resp.
91           60000).
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93       MAX_MEMBERS_PER_GROUP (number)
94           Maximum members per group entry. When the maximum is reached, a new
95           group entry (line) is started in /etc/group (with the same name,
96           same password, and same GID).
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98           The default value is 0, meaning that there are no limits in the
99           number of members in a group.
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101           This feature (split group) permits to limit the length of lines in
102           the group file. This is useful to make sure that lines for NIS
103           groups are not larger than 1024 characters.
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105           If you need to enforce such limit, you can use 25.
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107           Note: split groups may not be supported by all tools (even in the
108           Shadow toolsuite). You should not use this variable unless you
109           really need it.
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111       SYS_GID_MAX (number), SYS_GID_MIN (number)
112           Range of group IDs used for the creation of system groups by
113           useradd, groupadd, or newusers.
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115           The default value for SYS_GID_MIN (resp.  SYS_GID_MAX) is 101
116           (resp.  GID_MIN-1).
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FILES

119       /etc/group
120           Group account information.
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122       /etc/gshadow
123           Secure group account information.
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125       /etc/login.defs
126           Shadow password suite configuration.
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CAVEATS

129       Groupnames may contain only lower and upper case letters, digits,
130       underscores, or dashes. They can end with a dollar sign. Dashes are not
131       allowed at the beginning of the groupname. Fully numeric groupnames and
132       groupnames . or .. are also disallowed.
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134       Groupnames may only be up to 32 characters long.
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136       You may not add a NIS or LDAP group. This must be performed on the
137       corresponding server.
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139       If the groupname already exists in an external group database such as
140       NIS or LDAP, groupadd will deny the group creation request.
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EXIT VALUES

143       The groupadd command exits with the following values:
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145       0
146           success
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148       2
149           invalid command syntax
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151       3
152           invalid argument to option
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154       4
155           GID is already used (when called without -o)
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157       9
158           group name is already used
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160       10
161           can't update group file
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