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

Kubernetes Architecture

In the previous section, we gained a first impression of the core Kubernetes components: etcd, the API server, the scheduler, the controller manager, and the kubelet. These components, plus other add-ons, comprise the Kubernetes architecture, which can be seen in the following diagram:

Figure 2.8: Kubernetes architecture

At this point, we won't look at each component in too much detail. However, at a high-level view, it's critical to understand how the components communicate with each other and why they're designed in that way.

The first thing to understand is which components the API server can interact with. From the preceding diagram, we can easily tell that the API server can talk to almost every other component (except the container runtime, which is handled by the kubelet) and that it also serves to interact with end-users directly. This design makes the API server act as the "heart" of Kubernetes. Additionally...