Linux All-In-One For Dummies, 7th Edition

Chapter 3

Managing Users and Groups

IN THIS CHAPTER

Managing user accounts

Managing your groups

Working in the user environment

Changing user and group ownerships of files and directories

Linux is a multiuser system, so it has many user accounts. Even if you’ve set up a test machine and you’re the only user using that system, you’ll have a host of system user accounts. Most of these accounts aren’t for people to use; they’re for running specific programs, because many servers require a unique username and group name. The Apache web server, for example, often runs under the username apache.

User accounts can belong to one or more groups. Typically, each username has a corresponding private group name. By default, each user belongs to that corresponding private group, but you can define other groups for the purpose of providing access to specific files and directories based on group membership.

User and group ownerships of files ensure that only the right people (or the right processes) can access certain files and directories. Managing the user and group accounts is a typical task ...