Do you have a nagging feeling that your monitoring needs improvement, but you just aren't sure where to start or how to do it? Are you plagued by constant, meaningless alerts? Does your monitoring system routinely miss real problems? This is the book for you. Mike lays out a practical approach to designing and implementing an effective monitoring--from the application down to hardware in a datacenter, and everything between. Practical Monitoring will provide you with straight-forward strategies and tactics for designing and implementing a strong monitoring foundations for your company. Practical Monitoring has a unique vendor-neutral approach to monitoring. Rather than discuss how to implement specific tools, Mike teaches the principles and underlying mechanics behind monitoring so you can implement the lessons in any tool. Practical Monitoring covers such topics as: Monitoring antipatterns Principles of monitoring design How to build an effective on-call rotation Getting metrics and logs out of your application. From the Preface A Word on Monitoring Today Monitoring is a quickly evolving topic. To make things more challenging, monitoring is a topic that will never reach a state of true maturity: every time we get close, our entire world changes. In the late ’90s and early ’00s, Nagios was king, and we were all pretty satisfied with it. Before long, we needed to start automating infrastructure due to the growing size of it all. People began doing interesting things with scaling it (e.g., Gearman, instant failover with custom heartbeats and DRBD) and managing the configuration (e.g., external datasources, custom UIs, and MySQL-backed configuration storage), completely stretching Nagios to its limits and revealing that our ways of thinking about monitoring were beginning to show their age. This has been repeated a few times since then, of course: cloud computing, containers, microservices. While this constant change may frustrate some, it excites others. Take heart, though: the principles I will talk about are timeless. Who Should Read This Book If you deal with monitoring, this is the book for you. More specifically, this book is geared toward those seeking a foundational understanding of monitoring. It’s suitable for junior staff as well as nontechnical staff looking to beef up their knowledge on monitoring. If you already have a great grasp on monitoring, this probably is not the book for you. There are no deep dives into specific tools or discussions about monitoring at Google-scale. Instead, you will find practical, real-world examples and immediately actionable advice geared to those new to the world of monitoring. Those looking for the next hot monitoring tool to implement will be disappointed. As I will discuss later in this book, there’s no magic bullet for solving your monitoring challenges. As such, this book is tool-agnostic, though I certainly will mention specific tools from time to time as examples of what to do or not to do. Likewise, if you want to go deeper into a particular stack of tools, this book will not help. A minimum level of technical knowledge is assumed for this book. I assume you know the basics of running servers and writing code. My examples all reference Linux, though the topics are still generically applicable for Windows administrators as well.