Chef fact

Ohai is a tool that is used to collect system configuration data, which is provided to the chef-client for use within cookbooks. Ohai is run by the chef-client at the beginning of every Chef run to determine the system state. Ohai includes many built-in plugins to detect common configuration details as well as a plugin model for writing custom plugins.

The types of attributes Ohai collects includes

*Operating System 

*Network

*Memory

*Disk

*CPU

*Kernel

*Hostnames

*Fully qualified domain names

*Virtualization

*Cloud provider metadata

Attributes that are collected by Ohai are automatic level attributes, in that these attributes are used by the chef-client to ensure that these attributes remain unchanged after the chef-client is done configuring the node and some important directory are

*/opt/chef-server – The installation from the package is here.

*/etc/chef-server – The API-specific configuration files and keys are here.

*/var/opt/chef-server – The dependent services such as RabbitMQ, Nginx, PostgreSQL database, SOLR indexes are here.

*/var/log/chef-server – All the unit services write their output here.

Relevant Blogs:

Chef data bags 

Testing cookbook with Test kitchen 

Google Cloud Platform 

Create and manage docker networks