Use of groupadd for user and group management on the command line interface

Use of groupadd for user and group management on the command line interface

Groupadd-create a new group

The groupadd command is used to create a new group.

Syntax
Groupadd [options] group

Option:
-H for help

-G: create a user group with the specified GID

-P: Specify the group password when creating the group

-R -- system: creates a system user with the UID ranging from 1 to 499.

-O, -- non-unique allows repeated groups to be created

-F when creating a group, if the group exists, it also exits successfully.

-K, -- key 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.

I don't know why the-K option is used? Explanations

 

The following is an example.

# Groupadd xiao1

# Cat/etc/group | tail-1

Xiao1: x: 4039: information of the created group xiao1

# Groupadd-g 4040 xiao1

Groupadd: group 'xiao1' already exists creation failed

# Groupadd-g 4039 xiao2

Groupadd: GID '000000' already exists creation failed

# Groupadd-g 4040-o-f xiao1 created successfully

# Groupadd-g 4039-o-f xiao2 created successfully

Note: When-o-f is used together, a non-unique group can be created successfully. What are the benefits of doing so when I am a little white? Explanations