The groupmod command’s switches with example – Unix/Linux

The “groupmod” command modify a group definition on the system.
Syntax:

# groupmod [options] GROUPNAME

Switches with example:

1, -g, –gid GID
The group ID of the given GROUP will be changed to GID.
The value of GID must be a non-negative decimal integer. This value must be unique, unless the -o option is used. Values between 0 and 999 are typically reserved for system groups.
Any files that have the old group ID and must continue to belong to GROUP, must have their group ID changed manually.
Example:

----
[root@localhost ~]# grep megrp /etc/group
megrp:x:666:
megrp2:x:666:
----
[root@localhost ~]# groupmod -g 777 megrp2
[root@localhost ~]# grep megrp /etc/group
megrp:x:666:
megrp2:x:777:

2, -h, –help

Display help message and exit.

3, -n, –new-name NEW_GROUP

The name of the group will be changed from GROUP to NEW_GROUP name.
Example:

[root@localhost ~]# groupmod -n megrpnew megrp
[root@localhost ~]# grep megrp /etc/group
megrpnew:x:666:

4, -o, –non-unique

When used with the -g option, allow to change the group GID to a non-unique value.
Example:

[root@localhost ~]# groupmod -g 501 -o megrpnew
[root@localhost ~]# grep megrp /etc/group
megrpnew:x:501:

5, -p, –password PASSWORD
The encrypted password, as returned by crypt(3).
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.

That’s it!! 🙂

Related Links:
groupdel, groupmems, groupadd,

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