To control access to a Linux system and the data it contains, we need to do two things:
• We need to require users to supply a set of credentials before they will be granted access to the system.
• We need access controls that specify what individual users can do with files and directories in the file system after they have logged in.
We’re going to address the first condition in this chapter. To control overall access to the system itself, we need to implement users and groups. (The second condition will be addressed in a later chapter.) In this part of this chapter, we’re going to discuss how to do this. Specifically, we’re going to cover the following:
• Linux user accounts
• Linux groups
Let’s begin by ...