Book Image

Puppet 5 Essentials - Third Edition

By : Martin Alfke, Felix Frank
Book Image

Puppet 5 Essentials - Third Edition

By: Martin Alfke, Felix Frank

Overview of this book

Puppet is a configuration management tool that allows you to automate all your IT configurations, giving you control over what you do to each Puppet Agent in a network, and when and how you do it. In this age of digital delivery and ubiquitous Internet presence, it's becoming increasingly important to implement scaleable and portable solutions, not only in terms of software, but also the system that runs it. This book gets you started quickly with Puppet and its tools in the right way. It highlights improvements in Puppet and provides solutions for upgrading. It starts with a quick introduction to Puppet in order to quickly get your IT automation platform in place. Then you learn about the Puppet Agent and its installation and configuration along with Puppet Server and its scaling options. The book adopts an innovative structure and approach, and Puppet is explained with flexible use cases that empower you to manage complex infrastructures easily. Finally, the book will take readers through Puppet and its companion tools such as Facter, Hiera, and R10k and how to make use of tool chains.
Table of Contents (10 chapters)

Simplifying things using external facts

If writing and maintaining Ruby code is not desirable in your team for any reason, you might prefer to use an alternative that allows shell scripts, or really any kind of programming language, or even static data with no programming involved at all. Facter allows this in the form of external facts.

Creating an external fact is similar to the process used for regular custom facts, with the following distinctions:

  • External facts are produced by standalone executables or files with static data, which the agent must find in /etc/puppetlabs/facter/facts.d/
  • The data is not just a string value, but an arbitrary number of key=value pairs instead

The data need not use the ini file notation style; the key/value pairs can also be in the YAML or JSON format. The following external facts hold the same data:

# site-facts.txt