Book Image

Getting Started with Kubernetes, Second Edition - Second Edition

By : Jonathan Baier
Book Image

Getting Started with Kubernetes, Second Edition - Second Edition

By: Jonathan Baier

Overview of this book

Kubernetes has continued to grow and achieve broad adoption across various industries, helping you to orchestrate and automate container deployments on a massive scale. This book will give you a complete understanding of Kubernetes and how to get a cluster up and running. You will develop an understanding of the installation and configuration process. The book will then focus on the core Kubernetes constructs such as pods, services, replica sets, replication controllers, and labels. You will also understand how cluster level networking is done in Kubernetes. The book will also show you how to manage deployments and perform updates with minimal downtime. Additionally, you will learn about operational aspects of Kubernetes such as monitoring and logging. Advanced concepts such as container security and cluster federation will also be covered. Finally, you will learn about the wider Kubernetes ecosystem with OCP, CoreOS, and Tectonic and explore the third-party extensions and tools that can be used with Kubernetes. By the end of the book, you will have a complete understanding of the Kubernetes platform and will start deploying applications on it.
Table of Contents (20 chapters)
Title Page
Credits
About the Author
Acknowledgement
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface

DNS


DNS solves the issues seen with environment variables by allowing us to reference the services by their name. As services restart, scale out, or appear anew, the DNS entries will be updating and ensuring that the service name always points to the latest infrastructure. DNS is set up by default in most of the supported providers.

Note

If DNS is supported by your provider, but not set up, you can configure the following variables in your default provider config when you create your Kubernetes cluster:ENABLE_CLUSTER_DNS="${KUBE_ENABLE_CLUSTER_DNS:-true}"DNS_SERVER_IP="10.0.0.10" DNS_DOMAIN="cluster.local" DNS_REPLICAS=1

With DNS active, services can be accessed in one of two forms—either the service name itself, <service-name> or a fully qualified name that includes the namespace, <service-name>.<namespace-name>.cluster.local. In our examples, it would look similar to node-js-90 or node-js-90.default.cluster.local.