I asked a psychiatric nurse practitioner about paranoia, and was told that “paranoiais the feeling that people are after you.” A medical dictionary would give you a slightly different definition, but this one is actually terribly useful for any system administrator. It’s not that everyone on the Internet is trying to attack you, but there’s always someone who wants to break into your system. Even if you think you have nothing of value, someone wants to own your computer. And you won’t realize the value of what you have until someone else has it. That’s just human nature.

If you’re not paranoid on the Internet, you’re in trouble.

That’s where OpenBSD comes in.

This book is an introduction to the OpenBSD operating system. OpenBSD is a member of the BSD family of operating systems. It is widely regarded as the most secure operating system available anywhere, under any licensing terms. It’s widely used by Internet service providers, embedded systems manufacturers, and anyone who needs security and stability. If you’re an experienced Unix system administrator who wants to add OpenBSD to your repertoire, this book is for you.

When you finish this book, you should be comfortable working with OpenBSD. You will understand how to configure, troubleshoot, and upgrade computers running OpenBSD and have a basic understanding of OpenBSD’s software, security, and network management features.