We covered a lot of ground in this chapter, and hopefully you found some suggestions that you can actually use. We started out with showing you the dangers of always logging in as the root user and how you should use sudo, instead. In addition to showing you the basics of sudo usage, we also looked at some good sudo tips and tricks. We moved on to user management, by looking at how to lock down users' home directories, how to enforce strong password policies, and how to enforce account and password expiration policies. Then, we talked about a way to prevent brute-force password attacks, how to manually lockout user accounts, and set up security banners.

In the next chapter, we'll look at how to work with various firewall utilities. I'll see you there.