It is a powerful automation platform that provides a way to transforms infrastructure into code. Chef is a tool for which you write scripts that are used to automate processes. What processes? Pretty much anything related to IT.
Chef Server: The Chef Server is the central store of your infrastructure’s configuration data. The Chef Server stores the data necessary to configure your nodes and provides search, a powerful tool that allows you to dynamically drive node configuration based on data.
Chef Node: A Node is any host that is configured using Chef-client. Chef-client runs on your nodes, contacting the Chef Server for the information necessary to configure the node. Since a Node is a machine that runs the Chef-client software, nodes are sometimes referred to as “clients”.
Chef Workstation: A Chef Workstation is the host you use to modify your cookbooks and other configuration data. All the configurations are first tested in the Chef Workstation and then it is forwarded to the Chef Server.
A Resource represents a piece of infrastructure and its desired state, such as a package that should be installed, a service that should be running, or a file that should be generated. A block of Resource can be considered as a Recipe.
A Recipe is a collection of Resources that describes a particular configuration or policy. A Recipe describes everything that is required to configure part of a system.
A Node represents a server and is typically a virtual machine, container instance, or physical server – basically any compute resource in your infrastructure that is managed by Chef.
A Recipe is a collection of Resources, and primarily configures a software package or some piece of infrastructure. A Cookbook groups together Recipes and other information in a way that is more manageable than having just Recipes alone.
run-list lets you specify which Recipes to run, and the order in which to run them. The run-list is important when you have multiple Cookbooks, and the order in which they run matters.
Starter Kit will create the necessary configuration files like chef directory, knife.rb, the ORGANIZATION-validator.pem, and USER.pem files etc. with the correct information that is required to interact with the Chef server.
Chef is an automation tool for keeping infrastructure as code. It has many benefits. Some of these are as follows:
Cloud Deployment: We can use Chef to perform automated deployment in Cloud environment.
Multi-cloud support: With Chef we can even use multiple cloud providers for our infrastructure.
Hybrid Deployment: Chef supports both Cloud based as well as datacenter-based infrastructure.
High Availability: With Chef automation, we can create high availability environment. In case of hardware failure, Chef can maintain or start new servers in automated way to maintain highly available environment.
Chef is composed of many components like Chef Server, Client etc. Some of the main components in Chef are as follows:
Client: These are the nodes or individual users that communicate with Chef server.
Chef Manage: This is the web console that is used for interacting with Chef Server.
Load Balancer: All the Chef server API requests are routed through Load Balancer. It is implemented in Nginx.
Bookshelf: This is the component that stores cookbooks. All the cookbooks are stored in a repository. It is separate storage from the Chef server.
PostgreSQL: This is the data repository for Chef server.
Chef Server: This is the hub for configuration data. All the cookbooks and policies are stored in it. It can scale to the size of any enterprise.