Security is a very complex subject. So complex that no one person can become an all-knowing expert, as even the top people in the industry are continually learning. Likewise, it's statistically impossible to create a bulletproof server that cannot be compromised. But as a network administrator, you have a role in doing the best you can to keep your nodes as secure as you're able to. Security is often reactionary, which requires you to be on your toes. In this chapter, we took a look at some of the ways you can help safeguard your network from risks. We covered concepts such as securing SSH, limiting your attack surface, securing Apache with SSL, fail2ban, and deploying security updates.

In the next chapter, we'll look into things you can do to troubleshoot issues when things go wrong.