Until recently, learning CoreDNS required reading the code or combing through the skimpy documentation on the website. No longer. With this practical book, developers and operators working with Docker or Linux containers will learn how to use this standard DNS server with Kubernetes.

John Belamaric, senior staff software engineer at Google, and Cricket Liu, chief DNS architect at Infoblox, show you how to configure CoreDNS using real-world configuration examples to achieve specific purposes. You’ll learn the basics of DNS, including how it functions as a location broker in container environments and how it ties into Kubernetes.

• Dive into DNS theory: the DNS namespace, domain names, domains, and zones
• Learn how to configure your CoreDNS server
• Manage and serve basic and advanced zone data with CoreDNS
• Configure CoreDNS service discovery with etcd and Kubernetes
• Learn one of the most common use cases for CoreDNS: the integration with Kubernetes
• Manipulate queries and responses as they flow through the plug-in chain
• Monitor and troubleshoot the availability and performance of your DNS service
• Build custom versions of CoreDNS and write your own plug-ins

Table of Contents

Chapter 1. Introduction

Chapter 2. A DNS Refresher

Chapter 3. Configuring CoreDNS

Chapter 4. Managing Zone Data

Chapter 5. Service Discovery

Chapter 6. Kubernetes

Chapter 7. Manipulating Queries and Responses

Chapter 8. Monitoring and Troubleshooting

Chapter 9. Building a Custom Server

About the Authors

John Belamaric is an experienced software engineer and architect with over 20 years of software design and development experience. He works on the Google Cloud team, focused on Kubernetes and GKE. He is also a core maintainer of CoreDNS, a CNCF project that provides dynamic, DNS-based service discovery in Kubernetes and other container and cloud stacks.

He is a Senior Staff Software Engineer at Google, holds three patents, and is a co-author of "OpenStack Cloud Application Development".

Cricket Liu graduated from the University of California, Berkeley, that great bastion of free speech, unencumbered Unix, and cheap pizza. He joined Hewlett-Packard after graduation and worked for HP for nine years.

Cricket began managing the hp.com zone after the Loma Prieta earthquake forcibly transferred the zone's management from HP Labs to HP's Corporate Offices (by cracking a sprinkler main and flooding a Labs computer room). Cricket was hostmaster@hp.com for over three years, and then joined HP's Professional Services Organization to co-found HP's Internet Consulting Program.

Cricket left HP in 1997 to form Acme Byte & Wire, a DNS consulting and training company, with his friend Matt Larson. Network Solutions acquired Acme in June 2000, and later the same day merged with VeriSign. Cricket worked for a year as Director of DNS Product Management for VeriSign Global Registry Services.

Cricket joined Infoblox, a company that develops DNS, DHCP and IP Address Management solutions, in March, 2003. He is currently their Chief DNS Architect and a Senior Fellow. He's been reassured that they mean "senior" in the respectful sense, not in the "senior discount" sense.