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

Breakdown of components, variables, and artifacts

HCL templates rely on the declaration of sources and parameters, which are then invoked in a build declaration. The build block declares a list of sources to use and which provisioners to run on them. In this case, we’re defining just one source using the virtualbox-iso builder:

source "virtualbox-iso" "hello-base" {

Note that there are actually multiple builders that support VirtualBox: ISO, OVF, or VM. ISO is the standard way you might install a VirtualBox machine from a DVD image or ISO file. This slightly complicates our installation because we need two steps:

  1. Format and install a virtual hard disk.
  2. Boot from the new install and finish provisioners over SSH.

Once this image is built into an OVF output, it can be used as a quicker base image to try other build options, since no ISO installation will be necessary. Instead, the VirtualBox OVF builder can be used to rapidly create...