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

The Kubernetes Scheduler

As mentioned in the introduction, a typical cluster has several nodes. When you create a Pod, Kubernetes has to choose a node and assign the Pod to it. This process is known as Pod scheduling.

The Kubernetes component that is responsible for deciding which node a Pod should be assigned to for execution is called a scheduler. Kubernetes comes with a default scheduler that suffices for most use cases. For example, the default Kubernetes Scheduler spreads the load evenly in the cluster.

Now, consider a scenario in which two different Pods are expected to communicate with each other very often. As a system architect, you may want them to be on the same node to reduce latency and free up some internal networking bandwidth. The Scheduler does not know the relationship between different types of Pods, but Kubernetes provides ways to inform the Scheduler about this relationship and influence the scheduling behavior so that these two different Pods can be hosted...