|GROUPADD(8)||System Management Commands||GROUPADD(8)|
groupadd - create a new group
groupadd [OPTIONS] NEWGROUP
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.
The options which apply to the groupadd command are:
-g, --gid GID
See also the -r option and the GID_MAX description.
-K, --key KEY=VALUE
Example: -K GID_MIN=100 -K GID_MAX=499
Note: -K GID_MIN=10,GID_MAX=499 doesn't work yet.
-p, --password PASSWORD
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.
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
-P, --prefix PREFIX_DIR
The default behavior (if the -g, -N, and -U options are not specified) is defined by the USERGROUPS_ENAB variable in /etc/login.defs.
The following configuration variables in /etc/login.defs change the behavior of this tool:
GID_MAX (number), GID_MIN (number)
The default value for GID_MIN (resp. GID_MAX) is 1000 (resp. 60000).
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)
The default value for SYS_GID_MIN (resp. SYS_GID_MAX) is 101 (resp. GID_MIN-1).
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.
The groupadd command exits with the following values: