A classic organization has a minimum of two environments in which the infrastructure is run: development and production. Very often, a lot of environments are seen, such as staging, testing, alpha or beta. It's entirely up to the organization to model the infrastructure according to its needs, and the complexity can grow very quickly. The good news is that Chef helps a lot in mapping this model to the infrastructure. There's a set of information that will be different in two distinct environments, such as cookbook versions or attributes, and Chef makes it as easy as possible to manage these environments. By default, nodes without an environment set will run in a _default environment.

In this section, we'll see how to create different environments, how to set nodes (both existing and new) in a dedicated environment, how to set cookbook constraints, and finally how to override the attributes in each environment.