Chef in DevOps

Chef :

Chef is a tool for configuration Management and is closely competing with Puppet.

What is Chef ?

Chef is an automation tool that provides a way to define infrastructure as code infrastructure as code (IAC) simply means that managing infrastructure by writing code (Automating infrastructure) rather than using manual process.

Chef is a powerful automation platform that transforms infrastructure into code.

It comprise of:

• Chef workstation
• Chef client nodes
• Chef Server

Chef Components :

• Workstation
• Cookbook
• Ruby
• Node
• Chef Client
• Chef server
• Chef Supermarket

Workstation Components and Tools

• Development Kit
• Chef
• Knife
• Chef repo
• Kitchen
• Chefspec

Cookbook :

A Cookbook is the fundamental unit of configuration and policy distribution. A cookbook defines a scenario and contains everything that is required to support that scenario:
Recipes that specify the resources to use and the order in which they are to be applied
Attribute values 
File distribution
Extension to Chef, such as custom as custom resource and libraries                                                                                                             
Components :

1. Attributes
2. Files
3. Libraries
4. Metadata
5. Recipes
6. Resource
7. Templates
8. Tests

Ruby 

Ruby is the programming language that is the authoring for cookbooks. Most recipes are simple patterns (blocks that define properties and values that map to specific configuration items like packages, files, service, templates, and users). The full power of Ruby is available for when you need a programming language.

Nodes Components :

A node is any machine - physical, virtual, cloud, network device, etc. - that is under management by Chef.
Types :

• Server
• Cloud
• Virtual machine
• Network device
• container

Chef on Nodes :

They key components of nodes are under management by Chef include:

• Chef client
• Ohai