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

Creating Your First Template

What is learning a new tool without a Hello World app? Let’s make a basic Hello World template to break down the basic components of a template. HCL2 is the recommended format to write templates as of version 1.5, but for those who prefer JSON or encounter legacy JSON templates, we will build both HCL and JSON versions. We’ll keep this as simple as possible while demonstrating key features in a template that can be built on your own laptop in a coffee shop using free virtualization from Oracle VirtualBox. Coffee will come in handy while you wait for builds to run. We will cover the following topics:

  • Hello World template for a local VM
  • Breakdown of template components
  • Using an IDE to help you write templates
  • Applying the VirtualBox builder