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

Summary

In this chapter, you learned about custom controllers. As per the Kubernetes glossary, a controller implements a control loop to watch the state of the cluster through the API server and makes changes in an attempt to move the current state toward the desired state.

Controllers can not only watch and manage user-defined CRs, but they can also act on resources such as Deployments or services, which are typically part of the Kubernetes controller manager. Controllers provide a way to write your own code to suit your business needs.

CRDs are the central mechanism used in the Kubernetes system to extend its capability. CRDs provide a native way to implement custom logic for the Kubernetes API server that satisfies your business requirements.

You have learned about how CRDs and controllers help provide an extension mechanism for the Kubernetes platform. You have also seen the process through which you can configure and deploy custom controllers on the Kubernetes platform...