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Mastering Linux® System Administration
Christine Bresnahan
Richard Blum
Copyright © 2021 by John Wiley & Sons, Inc. All rights reserved.
Published by John Wiley & Sons, Inc., Hoboken, New Jersey.
Published simultaneously in Canada.
ISBN: 978‐1‐119‐79445‐5
ISBN: 978‐1‐119‐79447‐9 (ebk.)
ISBN: 978‐1‐119‐79446‐2 (ebk.)
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To the Lord God Almighty, “in whom are hidden all the treasures of wisdom and knowledge.”
—Colossians 2:3
Acknowledgments
First, all glory and praise go to God, who through His Son, Jesus Christ, makes all things possible and gives us the gift of eternal life.
Many thanks go to the fantastic team of people at John Wiley & Sons for their outstanding work on this project. Thanks to Kenyon Brown, the acquisitions editor, for offering us the opportunity to work on this book. Also, thanks to Kathryn Duggan, the project editor, for keeping things on track and making this book more presentable. Thanks, Kathi, for all your hard work and diligence. The technical editor, Jason Eckert, did a wonderful job of double‐checking all the work in the book, plus making suggestions to improve the content. Thanks to Barath Kumar Rajasekaran and his team for their endless patience and diligence to make our work readable. We would also like to thank Carole Jelen at Waterside Productions, Inc., for arranging this opportunity for us, and for helping us out in our writing careers.
Christine would like to thank her husband, Timothy, for his encouragement, patience, and willingness to listen, even when he has no idea what she is talking about. Rich would like to thank his wife, Barbara, for the life‐sustaining baked goods she readily prepared to help him keep up his energy while writing!
About the Authors
Christine Bresnahan started working with computers more than 30 years ago in the IT industry as a system administrator. Christine is an adjunct professor at Ivy Tech Community College where she teaches Linux certification and Python programming classes. She also writes books and produces instructional resources. During her downtime, Christine enjoys spending time with her husband and family, hiking, and gardening.
Richard Blum has worked in the IT industry for more than 30 years as both a systems and network administrator, working with lots of different operating systems (including Linux, of course). Over the years, he's also volunteered for several nonprofit organizations to help support small networks that had little financial support. Rich is the author of many Linux‐based books for total Linux geeks and teaches online courses in Linux and web programming. When he's not busy being a computer nerd, Rich enjoys playing piano and bass guitar and spending time with his wife, Barbara, and their two daughters, Katie Jane and Jessica.
About the Technical Editor
Jason W. Eckert is an experienced technical trainer, systems architect, software engineer, and best‐selling author in the technology industry. With 45 industry certifications, more than 30 years of technology and programming experience, 4 published apps, and 25 published textbooks covering UNIX, Linux, Security, Windows Server, Microsoft Exchange Server, PowerShell, BlackBerry Enterprise Server, and video game development, Mr. Eckert brings his expertise to every class that he teaches at triOS College. He was also named 2019 Outstanding Train‐the‐Trainer from the Computing Technology Industry Association (CompTIA). For more information about Mr. Eckert, visit jasoneckert.net.
Introduction
Over the last few decades, the Linux operating system has evolved from being a hobbyist curiosity to becoming the operating system of choice for most servers on the Internet. The explosion in popularity of cloud computing is due to the robustness of Linux servers,