Book Image

Puppet 5 Cookbook - Fourth Edition

By : Thomas Uphill
Book Image

Puppet 5 Cookbook - Fourth Edition

By: Thomas Uphill

Overview of this book

Puppet is a configuration management system that automates all your IT configurations, giving you control of managing each node. Puppet 5 Cookbook will take you through Puppet's latest and most advanced features, including Docker containers, Hiera, and AWS Cloud Orchestration. Updated with the latest advancements and best practices, this book delves into various aspects of writing good Puppet code, which includes using Puppet community style, checking your manifests with puppet-lint, and learning community best practices with an emphasis on real-world implementation. You will learn to set up, install, and create your first manifests with version control, and also learn about various sysadmin tasks, including managing configuration files, using Augeas, and generating files from snippets and templates. As the book progresses, you'll explore virtual resources and use Puppet's resource scheduling and auditing features. In the concluding chapters, you'll walk through managing applications and writing your own resource types, providers, and external node classifiers. By the end of this book, you will have learned to report, log, and debug your system.
Table of Contents (16 chapters)
Title Page
Packt Upsell
Contributors
Preface
Index

Drawing dependency graphs


Dependencies can get complicated quickly, and it's easy to end up with a circular dependency (where A depends on B, which depends on A) that will cause Puppet to complain and stop working. Fortunately, Puppet's --graph option makes it easy to generate a diagram of your resources and the dependencies between them, which can be a big help in fixing such problems.

Getting ready

Install the graphviz package to view the diagram files:

t@mylaptop ~ $ sudo puppet resource package graphviz ensure=installed
Notice: /Package[graphviz]/ensure: created
package { 'graphviz':
  ensure => '2.40.1-20.fc28',
}

How to do it...

Follow these steps to generate a dependency graph for your manifest:

  1. Create a new trifecta module:
t@burnaby $ pdk new module trifecta
pdk (INFO): Creating new module: trifecta

We need to create the metadata.json file for this module, so we're going to ask you 4 questions.
If the question is not applicable to this module, accept the default option shown after...