Conclusion

So that’s that. Our journey together is just about done. If I’ve done my part and you’ve done yours, then by now you should have picked up some serious Linux skills. In fact, if you’ve practiced enough, you should feel comfortable taking responsibility for many common server administration tasks, and employers should be comfortable hiring you to perform those tasks on their servers. But before we part, let’s spend a couple of minutes covering what you’ve learned and where it might take you next.

What you’ve learned

Organizing and absorbing all the many steps you took through Linux in Action is going to be a challenge. To make this review more useful, I’ll rearrange much of what you read into a half dozen high-level, in-demand themes:

• Virtualization
• Connectivity
• Encryption
• Networking
• Image management
• System monitoring

Virtualization

By working with virtual machines and containers back in chapter 2, you used virtualization to build sandbox computer environments where you can safely experiment with new tools and technologies. In chapters 6 and 9, you launched chroot sessions to recover broken configurations and file systems or to reset an authentication password. And with your understanding of virtualization technologies, along with the introduction to infrastructure orchestration from chapter 16, you’re just a step away from diving deeply into the worlds of enterprise cloud and container computing.

Connectivity

Remote connectivity played important roles in nearly every one of the book’s projects: from remote server management (chapter 3) to scripted archive backups (chapter 4), from provisioning web servers (chapter 7) and file sharing (chapter 8) to system monitoring (chapter 11). There aren’t a lot of critical administrative tasks that would be possible without the existence of safe and reliable connections. You’ve now got the core Linux tools you’ll need to create, manage, and troubleshoot those connections.

Encryption

Business processes that rely heavily on open networks like the internet are going to need ways to secure their data both in transit and at rest. At this point, you’re ready to answer that need through the use of encryption tools. You learned about SSH session encryption in chapter 3, encrypted network file sharing in chapter 8, website encryption and TLS certificates in chapter 9, and VPNs in chapter 10.

Networking

In a complex world, your organization will need sophisticated networking solutions to make stuff happen. (I mean good stuff, of course.) Linux certainly pulls its weight on the networking front, and in this book you learned how to use Linux as a platform to build complex connectivity solutions like VPNs and DMZs (chapter 10). You also saw how it’s possible to share data over a private network using NFS in chapter 12 and discovered a whole stack of network performance optimization tools in chapter 14.

Image management

You saw how complete images of a file system can be used for data backup and recovery. As you learned from cloning and sharing VirtualBox VMs in chapter 2, images are also important for server orchestration. You’ll discover that this will be especially true and useful in the cloud-based infrastructure management world.

System monitoring

In chapter 13, you explored the workings of ongoing system monitoring. You used monitoring tools to keep ahead of problems related to security and system performance, which are connected to the four core computer elements: CPU, memory, storage, and network. Is it all coming back to you now?

What’s next

If you came to this book with your own specific goals, then please, don’t let me stop you. Get to it. But if you’re looking for ideas for some next-level adventures, consider these:

• Number one (two and three): get practical hands-on experience. Hit the command line and don’t stop hitting it. Use it to manage anything from simple file transfers to viewing a video on your WiFi-connected laptop from a DVD in a drive on your desktop. As an added bonus, when you run the VLC video application from the command line, you’ll be shown all kinds of process output. Reviewing the output can help you figure out why a favorite movie suddenly failed in mid-view.
• Pull out an empty USB drive, and build yourself an emergency toolkit. Load it up with a Linux live-boot image the way you saw back in chapter 6, and add some of your favorite troubleshooting and recovery tools. Test it out at least once before you put it away in a drawer or car storage compartment.
• Dig deeper into Bash scripting. Track down online samples of scripts that use event handling, variables, loops, and inputs. Consider building scripts to automate any administration tasks you commonly perform. Vivek Gite’s comprehensive guide to Bash scripting is a good place to start: https://bash.cyberciti.biz/guide/Main_Page.
• Explore the world of encrypted storage drives using tools like eCryptfs and cryptsetup. If you carry sensitive data around with you on your laptop or USB drives, then you’ll want to seriously consider what might happen if your devices fall into the wrong hands.
• If you’ve got coding skills, you might want to open up the Linux kernel and add some customizations of your own. Of course, you’ll need to get Linus Torvalds on your side before your changes will be accepted into the official kernel, but you’re welcome to deploy your fork for your own use. And the process will teach you a lot about how Linux works under the hood.
• Apply your Linux server skills to the cloud world. You’ll be much more effective on AWS or even Azure now that you understand much of what drives cloud infrastructure. Not sure where to start? Manning definitely has you covered. There’s my book Learn Amazon Web Services in a Month of Lunches (2017), the Wittig brothers’ Amazon Web Services in Action, 2nd ed. (2018), Azure in Action (Chris Hay and Brian H. Prince, 2010), and Learn Azure in a Month of Lunches (Iain Foulds, 2018). Your choice.
• Embrace containers through technologies like Docker and Kubernetes. Considering the speed and scalability containers bring to the table, they’re the future of enterprise computing. Manning’s Kubernetes in Action (Marko Lukša, 2017), Docker in Action (Jeff Nickoloff, 2016), and Docker in Practice (Ian Miell and Aidan Hobson Sayers, 2016) are all great resources.

Resources

What? You want more? All right. But just this once.

You should certainly feel free to visit my own website, https://bootstrap-it.com, where you’ll find original content and details of my other books and courses, all certified as Linux- and cloud-friendly. Feel free to follow me on Twitter (@davidbclinton) and be among the first to hear about my next dark plans for world conquest.

Check out the Manning book forum for Linux in Action (https://forums.manning.com/forums/linux-in-action). If you’re having trouble with any of the book’s projects or just want to describe your latest successes, share them with the community. I keep a close watch on that forum, and I should be there when I’m needed.

Go online. Wonderful people have been contributing great documentation and guides for using Linux for decades now. There are far too many forums, blogs, IRC channels, Slack groups, and documentation sites to begin listing them here. But www.tldp.org/FAQ/Linux-FAQ/online-resources.html is a great place to start.

Your favorite internet search engine should be your first choice when looking for help. And don’t forget that (amazingly) man works on the internet pretty much the same way it does on the command line. The first result you get for a man selinux search in your browser should be the same man document you’d get in the shell.

I wish you great success in your Linux learning. Be and stay in touch!

DAVID CLINTON