Book Image

The Kubernetes Operator Framework Book

By : Michael Dame
1 (1)
Book Image

The Kubernetes Operator Framework Book

1 (1)
By: Michael Dame

Overview of this book

From incomplete collections of knowledge and varying design approaches to technical knowledge barriers, Kubernetes users face various challenges when developing their own operators. Knowing how to write, deploy, and pack operators makes cluster management automation much easier – and that's what this book is here to teach you. Beginning with operators and Operator Framework fundamentals, the book delves into how the different components of Operator Framework (such as the Operator SDK, Operator Lifecycle Manager, and OperatorHub.io) are used to build operators. You’ll learn how to write a basic operator, interact with a Kubernetes cluster in code, and distribute that operator to users. As you advance, you’ll be able to develop a sample operator in the Go programming language using Operator SDK tools before running it locally with Operator Lifecycle Manager, and also learn how to package an operator bundle for distribution. The book covers best practices as well as sample applications and case studies based on real-world operators to help you implement the concepts you’ve learned. By the end of this Kubernetes book, you’ll be able to build and add application-specific operational logic to a Kubernetes cluster, making it easier to automate complex applications and augment the platform.
Table of Contents (16 chapters)
1
Part 1: Essentials of Operators and the Operator Framework
4
Part 2: Designing and Developing an Operator
9
Part 3: Deploying and Distributing Operators for Public Use

Chapter 11: Case Study for Core Operator – Etcd Operator

In the previous chapter (as for most of this book), we discussed Operators as a tool for managing applications that are deployed on Kubernetes. For most use cases, this is the main purpose of an Operator. In other words, the Operator serves to automate the applications that are developed by an organization. These applications are the products offered to users, and automating them helps to ship them without any issues and keep users happy. Beyond that, Kubernetes itself is simply the underlying architecture. As a part of this, it's usually assumed that Kubernetes doesn't need any additional automation as would be provided by Operators. After all, it was a key point of the early chapters in this book that Operators are not functionally much different than the native suite of controllers that make up the Kubernetes control plane in the first place.

However, there are situations where an Operator can be used to...