02. Creating and Modifying Groups

Creating a Group

To create a group, use the groupadd command.

$ groupadd family
Specify group id (else, system will make one for you).
Force create a group, even if it already exists.
Change name of the group.
Allow duplicate groupnames to be created.
Create a system group ID (gid < 500).

Notice that there's an option to set the group ID to less than 500 with the -r option. All group ID's in this range are known a system processes and not real user-populated groups. You may check all current groups within the /etc/group file, which we'll go over in detail shortly.

Modifying a Group

To modify a group, use the groupmod command. Let's try renaming our family group to cousins.

$ groupmod -n cousins family

Deleting groups

To delete a group, simply use the groupdel command.

$ groupdel cousins

Here's some extra practice for using the above commands and options.

$ groupadd developers
# Check to see that the new group has been added
$ cat /etc/group
# Let's say we have a group with GID 1010 already
$ groupadd -g 1010 developers
# This should error out. Now let's allow duplicates
$ groupmod -o -g 1040 developers
# Rename 
$ groupmod -n cool-kids developers

Want to avoid becoming a code monkey?

The Pragramatic Programmer

Want to avoid becoming a code monkey? Try Good Practice

The Pragmatic Programmer illustrates the best practices and major pitfalls of many different aspects of software development.Whether you're a new coder, an experienced programmer, or a manager responsible for software projects, use these lessons daily, and you'll quickly see improvements in personal productivity, accuracy, and job satisfaction.

$ Check price
49.9949.99Amazon 4.5 logo(338+ reviews)

More Good Practice resources

Take your Linux skills to the next level!

Command Line Kung Fu

Take your Linux skills to the next level! Try Linux & UNIX

Command Line Kung Fu is packed with dozens of tips and practical real-world examples. You won't find theoretical examples in this book. The examples demonstrate how to solve actual problems. The tactics are easy to find, too. Each chapter covers a specific topic and groups related tips and examples together.

$ Check price
14.9914.99Amazon 4.5 logo(27+ reviews)

More Linux & UNIX resources