Have you ever been responsible for a server and had something go wrong? Ever been in a situation where you didn’t know what was causing the problem or how to figure it out? I think any of us who develop code, work in quality assurance, or administer systems have had this sort of experience. Sometimes problems appear that were never covered in a class or training session. Experience is an amazing teacher, but gaining that experience can be intimidating and sometimes painful. This book gives anyone working in DevOps a bit of a head start.
DevOps Troubleshooting: Linux Server Best Practices starts with a discussion of best practices in troubleshooting. This lays a good foundation for the rest of the book and should be read right away. If you don’t already know how to narrow down the location or source of a problem, how to communicate with others who may be affected or who can assist, or even where to start when a problem arises, the first chapter gives a solid plan to help you out. Most of the content of this chapter will seem obvious to people with experience, but they were not obvious to us when we started, and this information would have saved most of us a few headaches. Ideas like favoring quick, simple tests over slow and complex one, favoring past solutions that are known to work, and most importantly, understanding how the systems work before doing anything are vital. I like the advice about using the internet, but carefully, and resisting rebooting as a cure-all (because it doesn’t help you find the cause of the problem).
The chapters that follow are each focused on a specific type of problem. They include discussions of tips, tricks, and tools for diagnosing, and fixing issues. There are chapters that cover server slowness due to CPU, RAM, and Disk I/O issues, boot problems, full or corrupt disk issues, network problems, DNS server issues, email problems, web server problems, and database problems. There is even a chapter on diagnosing common hardware problems.
Experienced Linux server gurus may pick up a trick or two, but it is those who are new to working with Linux servers who are most likely to benefit from this book, and benefit in significant ways. The book doesn’t cover how to use Linux or how to set up your server, but it covers exactly what the title of the book says it will cover. For this reason, I consider this a perfect second Linux book for anyone who is relatively new to any aspect of DevOps with Linux.