Infrastructure as Code, 3rd Edition

Chapter 11. Building Servers as Code

A Note for Early Release Readers

With Early Release ebooks, you get books in their earliest form—the author’s raw and unedited content as they write—so you can take advantage of these technologies long before the official release of these titles. This will be the 11th chapter of the final book. Please note that the GitHub repo will be made active later on. If you have comments about how we might improve the content and/or examples in this book, or if you notice missing material within this chapter, please reach out to the editor at [e-mail].

Infrastructure as Code originally emerged as a way to configure servers. Systems administrators wrote shell, batch, and Perl scripts. CFEngine pioneered the use of declarative, idempotent DSLs for installing packages and managing configuration files on servers, and Puppet and Chef followed.

The popularity of containerized (cloud native) and serverless application runtimes has shifted attention away from servers to the level of stacks. But most organizations that have been in business for a while still have at least some workloads running on servers, whether physical, virtualized, or cloud-hosted.¹. Even a newer organization starting from scratch typically provisions servers as part of their application hosting clusters.

Within the component model I described in Chapter 6, a server can be viewed either as an IaaS resource or a special type of infrastructure component. IaaS platforms expose ...