Architecture

Chef includes several clients with the distribution:

• Chef Solo: is a client application that works entirely from on-disk data, and is a light-weight alternative to a full client-server configuration.
• Chef Client: is the client application that works with a Chef Server to persist data and download cookbooks. Chef Clients can also take advantage of Chef Server's search abilities to dynamically integrate your applications with the rest of your infrastructure.
• Knife: is the command line interface to Chef. Knife is primarily used to interact with the Chef Server API, and it can be used for local Chef Repository maintenance.
• Shef: is the interactive Chef shell. Shef allows you to write, run, and debug recipes interactively and also provides a programmatic interface for viewing and editing data on your Chef Server.

The Chef Server that the Chef Client interacts with is either:

Hosted Chef

• Hosted Chef customers do not need to manage their Chef Server, as that is done for them by Opscode.
• If you are a Hosted Chef Customer and have a question, please contact support@opscode.com.

Private Chef

• Private Chef customers should refer to their separate Private Chef Administration Documention for the Private Chef Server.
• If you are a Private Chef Customer and have a question, please contact support@opscode.com.

Open Source Chef Server

• An Open Source Chef Server is comprised of the following components:
  • Chef Server: services HTTP API requests from the Web UI, nodes, and other clients (see above).
  • Chef Server Web UI: the web-based management console for the Chef Server. It manages your infrastructure by making API calls to Chef Server.
  • CouchDB: the primary data store for a Chef server.
  • RabbitMQ: stores and then forwards data from Chef Server to the Chef Solr Indexer. It acts as a buffer for cases when high write loads temporarily exceed the ability of the Chef Solr Indexer to update the search index.
  • Chef Solr Indexer: flattens and expands data to enhance searchability, then writes the data to Chef Solr.
  • Chef Solr: a thin wrapper around the Apache Solr search engine. Chef Solr allows you to find your way around your infrastructure by querying its metadata.