The use of computers have made our lives easier and, in some ways, more complicated. For example, if you own a PC, you likely have created a user name and password to access your computer, your files and several online accounts. Most of us have several accounts and thus have several different user names and passwords that we need to memorize. However, you are here because you are not most people. You are one of the few who use a Linux operating system and are intrigued to know how Linux PAM works. As you are well aware, usernames and passwords, finger scans, security questions and the like, are used to authenticate users to applications, services and servers. Applications need to communicate with services or servers to authenticate their users, and the authentication process can be complicated.

For security reasons, system administrators often change the way their servers authenticate users. When the authentication scheme changes, an application’s code needs to be recompiled to meet the new criteria. This need is where Linux PAM - or pluggable authentication modules - comes in. It’s the middleman between apps used by Linux and the server’s new authentication scheme. It allows the app to continue authenticating its users without having its code changed every time the authentication scheme is updated. This course is designed to help you understand how Linux PAM works. You will start by learning how to download and install Linux on your computer using Oracle VirtualBox as your virtual machine. Even if you already know how to do that yourself, you will likely learn something new from the instruction videos. Next, you will learn what PAM is, how it communicates with a server, and why it is a dominant and powerful tool for Linux users.

You will study how to determine whether or not an app is PAM-aware; that is, if an application uses PAM to authenticate its users. Study how the PAM file configuration format is designed. When you open any service file, you will see that the file is divided into three columns. The first column is the module interface (management or group type), the second column is for control flags, and the third column is the modules (SO file). Explore the function of these three columns in authenticating users. Become familiar with the authentication tasks that the four independent management groups in the first column perform. Understand the instructions given by the four flags in the control flags column, and comprehend how PAM can take an argument and pass it through a module in the third column. If you are a Linux user, or you have been given the task to administrate PAM for your organization, this is the course for you.