AWS System Administration

Chapter 10. DNS with Route 53

The venerable Domain Name System remains a critical component in the knowledge toolbox of a system administrator. Amazon’s Route 53 service can provide a tighter integration between DNS and other AWS systems such as Elastic Load Balancers and the Elastic Compute Cloud. Although DNS is incredibly simple at its core, a broken or misconfigured DNS server can result in some very interesting problems. Kris Buytaert, one of the original proponents of the DevOps movement, highlights this with the title of his blog: Everything Is a Freaking DNS Problem.

This book assumes that our readers are already familiar with the general concepts surrounding DNS. This chapter therefore focuses on the AWS-specific implementation provided by Route 53, and demonstrates a few techniques that can be used to configure a cloud-aware DNS service.

Creating DNS records to identify the server entry points of an application enables a smoother user experience for your internal users or developers, even when it is not downright required by external public access. It also enables you as the operator to easily replace published entry points with more powerful resources, without having to explicitly inform users of a change taking place. By redirecting a service-specific domain name record to a more powerful instance (or even a load-balancer), an administrator can perform but with a sleight of hand the magic trick of having all users march in a different direction from the one they used a ...