Writing Your First Manifests

Configuration management has become essential to the IT world. Faster development using agile methods has a huge impact on IT operations that need to keep pace with the faster deployment of systems. Server operations in general are hardly even feasible without a robust management infrastructure. Among the available tools, Puppet has established itself as one of the most popular and widespread solutions. Originally written by Luke Kanies, the tool is now distributed under the terms of Apache License 2.0 and maintained by Luke's company, Puppet Inc. It boasts a large and bustling community, rich APIs for plugins and supporting tools, outstanding online documentation, and a great security model based on SSL authentication.

Like all configuration management systems, Puppet allows you to maintain a central repository of infrastructure definitions, along with a toolchain to enforce the desired state on the systems under management. The whole feature set is quite impressive. This book will guide you through some steps to quickly grasp the most important aspects and principles of Puppet.

In this chapter, we will cover the following topics:

• Getting started
• Introducing resources, parameters, and properties
• Interpreting the output of the puppet apply command
• Using variables
• Adding control structures in manifests
• Controlling the order of execution
• Implementing resource interaction
• Examining Puppet core resource types