Book Image

The Kubernetes Workshop

By : Zachary Arnold, Sahil Dua, Wei Huang, Faisal Masood, Mélony Qin, Mohammed Abu Taleb
Book Image

The Kubernetes Workshop

By: Zachary Arnold, Sahil Dua, Wei Huang, Faisal Masood, Mélony Qin, Mohammed Abu Taleb

Overview of this book

Thanks to its extensive support for managing hundreds of containers that run cloud-native applications, Kubernetes is the most popular open source container orchestration platform that makes cluster management easy. This workshop adopts a practical approach to get you acquainted with the Kubernetes environment and its applications. Starting with an introduction to the fundamentals of Kubernetes, you’ll install and set up your Kubernetes environment. You’ll understand how to write YAML files and deploy your first simple web application container using Pod. You’ll then assign human-friendly names to Pods, explore various Kubernetes entities and functions, and discover when to use them. As you work through the chapters, this Kubernetes book will show you how you can make full-scale use of Kubernetes by applying a variety of techniques for designing components and deploying clusters. You’ll also get to grips with security policies for limiting access to certain functions inside the cluster. Toward the end of the book, you’ll get a rundown of Kubernetes advanced features for building your own controller and upgrading to a Kubernetes cluster without downtime. By the end of this workshop, you’ll be able to manage containers and run cloud-based applications efficiently using Kubernetes.
Table of Contents (20 chapters)
Preface

How the Components of Kubernetes Work Together to Achieve High Availability

You have learned in Chapter 2, An Overview of Kubernetes, how the pieces of Kubernetes work together to provide a runtime for your application containers. But we need to investigate deeper how these components work together to achieve high availability. To do that, we'll start with the memory bank of Kubernetes, otherwise known as etcd.

etcd

As you have learned in earlier chapters, etcd is the place where all Kubernetes configuration is stored. This makes it arguably the single most important component of the cluster since changes in etcd affect the state of everything. More specifically, any change to a key-value pair in etcd will cause the other components of Kubernetes to react to this change, which could mean disruptions to your application. In order to achieve high availability for Kubernetes, it is wise to have more than one etcd node.

But many more challenges arise when you add multiple...