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

Upgrading Kubernetes Worker Nodes

Although Kubernetes supports compatibility between master (API server) and worker nodes (kubelet) within one minor version, it is highly recommended that you upgrade the master and worker nodes in one go. Using kops, upgrading worker nodes is similar to upgrading master nodes. Due to the backward compatibility within one minor version, the worker nodes may still work if they are not version-matched by the master nodes, but it is strongly discouraged to run different versions of Kubernetes on worker and master nodes since this may create problems for the cluster.

However, the following considerations are of extreme importance if you want to keep your application online during the upgrade:

  • Make sure that your applications are configured to be highly available. This means that you should have at least two pods, each on different nodes, for each of your applications. If this is not the case, your applications may experience downtime once you...