David Clinton - Linux Security Fundamentals

David Clinton

Copyright 2021 by John Wiley & Sons, Inc., Indianapolis, Indiana

Published simultaneously in Canada

ISBN: 978-1-119-78146-2
ISBN: 978-1-119-78157-8 (ebk)
ISBN: 978-1-119-78156-1 (ebk)

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I would like to thank my wife for all her help and support through the long and demanding process of writing these books. And, once again, Im indebted to all the great people at Wiley who helped me turn a plain old manuscript into a great teaching tool.

David Clinton is a Linux server admin and AWS Solutions Architect who has worked with IT infrastructure in both academic and enterprise environments. He has authored technology booksincluding AWS Certified Solutions Architect Study Guide: Associate SAA-C01 Exam, Third Edition (Sybex, 2020) and the Ubuntu Bible (Wiley, 2020)and created more than 25 video courses teaching AWS and Linux administration, server virtualization, and IT security for Pluralsight.

In a previous life, David spent 20 years as a high school teacher. He currently lives in Toronto, Canada with his wife and family and can be reached through his website: https://bootstrap-it.com.

Ben Piper is a cloud and networking consultant who has co-authored multiple AWS study guides, including the AWS Certified Solutions Architect Study Guide: Associate SAA-C01 Exam, Second Edition (Sybex, 2019) and the AWS Certified Cloud Practitioner Study Guide: CLF-C01 Exam (Sybex, 2019). Hes also created more than 20 technology training courses covering Amazon Web Services and Cisco routing and switching. You can contact Ben by visiting his website: https://benpiper.com.

Right off the top, Id like to be clear about exactly what this book is and what its not. Linux Security Fundamentals is a guide to security best-practices for Linux admins. It is not however a comprehensive guide to deploying secure workloads in Linux environments.

So dont expect a lot of nuts and bolts demonstrations of complex administration tasks. Were not even going to cover the core basics of the Linux command line. Ill assume youve got all that already. This isnt a very technical book. In fact, there may be one or two chapters that dont even specifically mention Linux.

We wont talk, say, about the detailed configuration settings controlling cgroups or setting up effective and bullet-proof Nagios serversas important as they are. For that kind of detail, you can consult Chris Negus Linux Bibleor the Ubuntu Bible that I wrote in collaboration with Chris.

Instead, this book will quickly deliver the big-picture security knowledge that every admin should know (but often doesnt). The trick here, is that all that knowledge will delivered within a Linux context. So, for instance, along with the big-picture stuff you can expect to learn how to install the OpenVAS vulnerability scanner, construct a firewall using iptables, or build a custom Wireguard VPN. But dont expect to find that kind of technical detail in every chapter.

Why is a book like this necessary?

The moment we connect our phones, laptops, and servers to the internet, were all living in a very dangerous neighborhood. And theres no single set-it-and-forget-it solution thatll reliably keep all the looming threats away. The only way you can even hope to protect yourself and your digital resources is to understand the kinds of vulnerabilities that could affect your infrastructure and the ways smart administration can maximize both harm prevention and mitigation. But theres more. Since the IT threat landscape changes so often, youll also need to learn how to continuously monitor your infrastructure and keep up with developments in the technology world.

Whether youre a professional Linux admin, a developer, a data engineer, or even just a regular technology consumer, youll be both safer and more effective at everything you do if you can understand and apply security best practices. And considering how Linux has come to dominate the web application, DevOps, internet of things, and mobile connectivity industries, getting security right on Linux is more critical than ever before.