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

Highly Available Applications Running on Top of Kubernetes

Now that you've had a chance to spin up an EKS cluster and learn about Ingress, let's introduce you to our application. We have provided an example application that has a flaw that prevents it from being cloud-native and really being able to be horizontally scaled in Kubernetes. We will deploy this application in the following exercise and observe its behavior. Then, in the next section, we will deploy a modified version of this application and observe how it is more suited to achieve our stated objective of being highly available.

Exercise 12.03: Deploying a Multi-Replica Non-HA Application in Kubernetes

In this exercise, we will deploy a version of the application that's not horizontally scalable. We will try to scale it and observe the problem that prevents it from being scaled horizontally:

Note

We have provided the source code for this application in the GitHub repository for reference. However...