Learning CFEngine 3

Chapter 5. The CFEngine Design Center

The CFEngine Design Center is a repository of pre-made, ready-to-use components called sketches that allow entirely data-driven system management. You can install, configure, and deploy sketches across your infrastructure without modifying or even looking at the code used to implement them. Sketches may range in complexity from simple system-configuration tasks (e.g., configuring the system timezone) to complex, multi-host operations (e.g., coordinating and managing cloud instances in Amazon EC2).

You may wonder what the difference is between the CFEngine Design Center and the CFEngine Standard Library. The latter contains reusable but low-level building blocks that you use on your own policies to perform certain common tasks. Most bundles and bodies in the Standard Library have very limited scope and functionality: editing or copying files, defining classes, etc. By contrast, the Design Center contains more encompassing components that perform complete tasks that can stand on their own, such as configuring DNS, setting up the system timezone, installing MySQL, or managing EC2 virtual machines. Most Design Center sketches use the Standard Library in their code, just like any other policy.

The Design Center also provides tools for managing and creating sketches, and a framework for encapsulating your own policies, for your own use or to share with the community. The Design Center is a community project hosted on GitHub, so you are encouraged to ...