Linux security is not a chapter in a book, it is a way of life. For every task that you carry out in CentOS, you should consider the security impact and how your actions can be made more secure. Of course, security takes many forms, and much of it is quite simple (for example, the physical security of servers locked in server rooms and so on. In this section, we will visit the world of pluggable authentication modules (PAM) and SELinux. Do not be scared of either, especially, SELinux; they are your friends. In this chapter, we will cover the following topics:
Understanding PAM configuration files: At the heart of PAM are the files located in
/etc/pam.d; I will lead you through their syntax and meaningLimits of PAM: Through PAM's limits module, we can restrict limits on system resources that can be obtained in a user session
SELinux: This is a quick guide to SELinux, both through the filesystem and the user's perspective
Hardening Linux: This is a checklist on...