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

Docker container image format

Docker revolutionized container image management when it solved the container image de-duplication problem with hashed and overlayed images. During each step of a build, a checksum is generated for the image. If more than one image shares a layer or group of files, then there is no need to store them multiple times. This is a much more efficient way to store artifacts with shared dependencies compared to LXD containers.

Docker donated quite a bit of core technology to the CNCF foundation, with the container image format being part of the Container Native Initiative. A lot of traditional Docker containers you may be familiar with are now considered version 1, with version 2 extending a backward-compatible extension of version 1. Version 2 has become the standard for OCI projects, including Podman and newer releases of Docker. Note that a Podman builder is available as an external plugin that is based on the Docker plugin. Podman was built using Cgroups...