CloudFormation

CloudFormation Simplified:

CloudFormation is an automated tool for provisioning entire cloud-based environments. It is similar to Terraform where you codify the instructions for what you want to have inside your application setup (X many web servers of Y type with a Z type DB on the backend, etc). It makes it a lot easier to just describe what you want in markup and have AWS do the actual provisioning work involved.

CloudFormation Key Details:

• The main use case for CloudFormation is for advanced setups and production environments as it is complex and has many robust features.
• CloudFormation templates can be used to create, update, and delete infrastructure.
• The templates are written in YAML or JSON
• A full CloudFormation setup is called a stack.
• Once a template is created, AWS will make the corresponding stack. This is the living and active representation of said template. One template can create an infinite number of stacks.
• The Resources field is the only mandatory field when creating a CloudFormation template
• Rollback triggers allow you to monitor the creation of the stack as it’s built. If an error occurs, you can trigger a rollback as the name implies.
• AWS Quick Starts is composed of many high-quality CloudFormation stacks designed by AWS engineers.
• An example template that would spin up an EC2 instance:

• For any Logical Resources in the stack, CloudFormation will make a corresponding Physical Resources in your AWS account. It is CloudFormation’s job to keep the logical and physical resources in sync.
• A template can be updated and then used to update the same stack.