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About the Authors
David Clinton is a Linux server admin and AWS Solutions Architect who has worked with IT infrastructure in both academic and enterprise environments. He’s administrated physical systems, containers, and networks using many Ubuntu flavors for more than a dozen years. He has authored technology books—including AWS Certified Solutions Architect Study Guide: Associate SAA-C01 Exam (Sybex, 2020)—and created tens of video courses for Pluralsight teaching Amazon Web Services and Linux administration, server virtualization, and IT security.
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: www.bootstrap-it.com .
Chris Negus is a principal technical writer for Red Hat, Inc. In his decades of working with Linux and UNIX, Chris has taught hundreds of IT professionals to become certified Linux engineers, and he has written scores of documents on everything from Linux to virtualization to cloud computing and containerization.
Chris has also written and contributed to dozens of books on Linux and UNIX, including the Linux Bible (all editions), Linux Troubleshooting Bible, Red Hat Linux Bible (all editions), Docker Containers, CentOS Bible, Fedora Bible, Linux Toys, and Linux Toys II. Chris also co-authored several books for the Linux Toolbox series for power users: Ubuntu Linux Toolbox, Fedora Linux Toolbox, SUSE Linux Toolbox, Mac OS X Toolbox, and BSD UNIX Toolbox.
Before becoming an author and educator, Chris worked for eight years with the organization at AT&T that developed the UNIX operating system before moving to Utah to help contribute to Novell’s UnixWare project in the early 1990s. When not writing about Linux, Chris enjoys playing soccer, hanging out with his wife, Sheree, and spending what time he can with his sons, Seth and Caleb.
About the Technical Editor
Jason W. Eckert is an experienced technical trainer, consultant, and best-selling author in the technology industry. With 45 industry certifications, over 30 years of technology and programming experience, 4 published apps, and 25 published textbooks covering topics such as 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 www.jasoneckert.net.
Acknowledgments
Looking through the chapters of this book forces me to wonder at the size and ambition of the world of open source software. And that makes me think about all the thousands of developers, admins, architects, and—yes—writers who make this vast universe possible. This book is a testament to the hard work and community spirit of those individuals.
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, I’m indebted to all the great people at Wiley who helped me turn a plain old manuscript into a great teaching tool.
—David Clinton
When I was hired at Red Hat about a dozen years ago, I didn’t know that the organization would grow to about seven times its size, be bought by IBM for $34 billion, and (so far) still maintain the spirit of openness and excitement that it had when I first signed on. Every day when I come to work, I interact with many of the greatest Linux and cloud developers, testers, instructors, and support professionals in the world.
While I can’t thank everyone individually, there are a few people that I want to acknowledge in particular. I have the good fortune to take on so many cool and challenging projects because of the freedom that I receive from the people to whom I report at work. They include Michelle Bearer, Dawn Eisner, and Sam Knuth. Sam in particular has had my back and encouraged my work for more than a decade.
In my daily work, I want to give a shout out to my incredibly talented colleagues Scott McCarty, Ben Breard, Laurie Friedman, Dave Darrah, Micah Abbott, Steve Milner, Ian McLeod, Tom McKay, Joey Schorr, Bill Dettelback, Richa Marwaha, and Dirk Herrmann. Finally, a special thank you to Vikram Goyal, who luckily lives in Australia, so he is always available to bail me out when I blow up git in the middle of the night.
When it comes to support for writing this book, I have had the luxury of an excellent technical editor: Jason Eckert. He also worked on my most recent edition of The Linux Bible, and his broad experience with Linux systems has helped immensely. As for Devon Lewis, Kelly Talbot, and the people at Wiley, thanks for letting me continue to develop and improve this book over the years. Thanks also to Margot Maley Hutchison from Waterside Productions for contracting the book for me with Wiley and always looking out for my best interests.
Finally, thanks to my wife, Sheree, for sharing her life with me and doing such a great job raising Seth and Caleb.
—Christopher Negus
Contents at a Glance
Chapter 14: Administering Networking
Introduction
You can’t learn Ubuntu without using it. But if you’re ready for some serious hands-on research and experimentation, you can go a long way with this book. The Ubuntu Linux Bible is based on the 10th edition of Linux Bible, but has been refocused to ensure everything will work specifically on Ubuntu “right out of the box.”
Ubuntu may be the world’s most popular all-purpose Linux distribution. Canonical, the company that stands behind Ubuntu, reports that “Ubuntu powers millions of PCs worldwide.” It describes it as “the world’s most popular operating system across public clouds and OpenStack clouds” and “the #1 OS for containers.” In fact, as of this writing, of the more than a million virtual server instances currently running on the Amazon Web Services cloud, more than 32 percent are standalone Ubuntu installations (the total number, when you include Bitnami stacks, is probably closer to 60 percent). Compare that to Microsoft Windows share of 6 percent and the 2 percent attributed to Red Hat Enterprise Linux (see www.thecloudmarket .com/stats).
Ubuntu has become such an industry standard that when Microsoft released its Windows Subsystem for Linux feature back in 2016, Ubuntu was the only Linux distribution initially available.
Most of the skills we’ll learn here will transfer well to other Linux distributions—and especially to distros like Debian, Mint, and Kali Linux that share upstream sources with Ubuntu. So if you’re looking to get in on the action, stick around for the whole thing.
Beginner to certified professional: As long as you have used a computer, mouse, and keyboard, you can reach good places using this book. We’ll show you how to get and install Ubuntu, quickly put it to productive use, use it to solve critical problems and build powerful server environments, and ultimately excel at administering and securing it.
System administrator focused: When you’re finished with this book, you will know how to use, modify, and maintain Ubuntu. Almost all of the topics needed to achieve one or more Linux administration certifications are covered in this book. That said, many software developers and hobbyists will also enjoy it as they work to improve their skills.
Emphasis on command-line tools: Although point-and-click graphic interfaces are as good or better as anything else these days, many advanced features can only be utilized by entering commands and editing configuration files manually. We’ll mostly focus on mastering the Linux command-line shell.
Many, many demos and exercises: Instead of just telling you what Ubuntu does, we actually show you what it does. Then, to make sure that you’ve nailed it, you’ll have the opportunity to try it yourself. Every procedure and exercise has been tested to work in Ubuntu.
Ubuntu Linux Bible includes in-depth discussions covering server virtualization, infrastructure orchestration, and managing cloud and containerized applications (individually or at scale):
Cockpit administration web UI: Since the dawn of the Linux age, people have struggled to develop simple graphical or browser-based interfaces for managing Linux systems. Cockpit may well have finally delivered a way to manage the basic Linux features through its web UI. Throughout this book, Cockpit will be our graphic tool of choice. With Cockpit, you can now add users, manage storage, monitor activities, and do many other administrative tasks through a single interface.
Cloud technologies: Our coverage will include setting up your own Linux host for running virtual machines and running Linux in a cloud environment, such as Amazon Web Services. Linux is at the heart of most technological advances in cloud computing today. That means you need a solid understanding of Linux to work effectively in tomorrow’s data centers. The first chapters will cover all the Linux basics, which you’ll use through our various cutting-edge virtualization, networking, and storage administration exercises.
Ansible: Automating tasks for managing systems is now an unavoidable part of modern digital administration. Using Ansible, you can create playbooks that define the state of a Linux system. This includes things like setting which packages are installed, which services are running, and how features are configured. A playbook can configure one system or a thousand systems, be combined to form a set of system services, and be run again to return a system to a defined state. We’ll get introduced to Ansible, create our first Ansible playbook, and run ad-hoc Ansible commands.
Containers: Packaging and running applications in containers is becoming the preferred method for deploying, managing, and updating small, scalable software services and features. You’ll learn how to pull container images, run them, stop them, and even build your own container images using LXD and Docker.
Kubernetes: While containers are nice on their own, to be able to deploy, manage, and upgrade containers in a large enterprise, you need an orchestration platform. The Kubernetes project provides a powerful platform for just that purpose.
How This Book Is Organized
The book is organized to enable you to start off at the very beginning with Linux and grow to become a professional Ubuntu system administrator and power user.
