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)
1
Part 1: Packer’s Beginnings
7
Part 2: Managing Large Environments
11
Part 3: Advanced Customized Packer

The Power of Provisioners

So far, we have covered the basics of Packer templates and builders with a basic provisioner. Builders allow integrations to external platforms, hypervisors, and cloud providers via API integrations. Most likely, an image will need some runtime configuration before it’s saved and deployed. In this chapter, you will learn about the different types of provisioners available and what options you have to add artifacts or run tasks in a container or image. Common provisioners include local files or folders that should be uploaded to the image as well as scripts or processes that should be run as part of the building. The goal of provisioners is to minimize the work that needs to be done at runtime once an image is deployed. Classic examples of provisioners include these:

  • Installing to disk from classic install media, ISO, or network boot
  • Applying installation profiles, kickstarts, jumpstarts, or package groups
  • Running Ansible playbooks, Chef...