Book Image

HashiCorp Packer in Production

By : John Boero
Book Image

HashiCorp Packer in Production

By: John Boero

Overview of this book

Creating machine images can be time-consuming and error-prone when done manually. HashiCorp Packer enables you to automate this process by defining the configuration in a simple, declarative syntax. This configuration is then used to create machine images for multiple environments and cloud providers. The book begins by showing you how to create your first manifest while helping you understand the available components. You’ll then configure the most common built-in builder options for Packer and use runtime provisioners to reconfigure a source image for desired tasks. You’ll also learn how to control logging for troubleshooting errors in complex builds and explore monitoring options for multiple logs at once. As you advance, you’ll build on your initial manifest for a local application that’ll easily migrate to another builder or cloud. The chapters also help you get to grips with basic container image options in different formats while scaling large builds in production. Finally, you’ll develop a life cycle and retention policy for images, automate packer builds, and protect your production environment from nefarious plugins. By the end of this book, you’ll be equipped to smoothen collaboration and reduce the risk of errors by creating machine images consistently and automatically based on your defined configuration.
Table of Contents (18 chapters)
Part 1: Packer’s Beginnings
Part 2: Managing Large Environments
Part 3: Advanced Customized Packer

Hello World template for a local VM

A basic template requires just one builder. We could add data sources to look up external records or use variables to make the template reusable, but we will start basic and refactor it, adding more features later. Each type of builder has different options and parameters, so make sure to check the documented options on Packer’s website or via the Packer help menu. Also, we will do a deep dive into builders in Chapter 6, Working with Builders.

The Packer documentation is available at

Some options are mandatory, and some are optional. We will use comments as appropriate to indicate which is which for the virtualbox-iso builder. For convention, I like to use # as a comment when disabling a line of code, and // or /* when writing actual comments. I will break down the meaning of each part for a build of a CentOS Stream base image.

Full copies of these templates can be found at the GitHub repository here: https...