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

Basics of Go

If you have never coded in Go before, I’ll try to sum it up for you without offending the Go experts. Go is an open source programming language from Google inspired by C and C++ but featuring memory protection and automatic management of memory for the stack and heap. As a coder, this means you don’t need to worry much about how you use memory but the Go runtime may take some extra time to rearrange or garbage-collect memory. Unlike scripting, it also means your code must have no syntax errors and compile successfully to build a binary. This includes strong static types and complete syntax during compilation. The good news is that performance and stability for Go are very good compared to scripting, which must be parsed and type-checked every time you run it. Go’s performance is occasionally affected by memory garbage collection performed by the runtime, which scripts must also do anyway.

Goroutines are a simple mechanism for concurrency via lightweight...