Mastering Linux System Administration

Chapter 13Managing Users and Groups

At the core of Linux security is the user account. Each individual who accesses a Linux system should have a unique account assigned to them. Adding, modifying, and deleting user account authorizations are some of the most basic, but important, tasks you do to protect your system. Access granted to user accounts are more easily managed by putting the various accounts into groups. Managing these groups of users and defining what they are allowed to access also provides base‐level protection.

In addition to these user accounts and groups, it is important to understand basic Linux file and directory permissions, including how to view them and interpret their meanings. The codes used to set and modify permissions ...