CloudFormation

Infrastructure as Code

Infrastructure is described with code
This can be deployed in the cloud in order to create/update/delete the necessary resources

CloudFormation is a declarative way of outlining AWS infrastructure for any resources
In the CloudFormation templates we specify the resources needed to be instantiated
CloudFormation will create those in the right order with exact configuration that we specify

Infrastructure as code:
- No resources are manually created, which is excellent for control
- Code can be version controlled
- Changes to the infrastructure are reviewed through code
Cost:
- Each resource within a CloudFormation stack is tagged with an identifier, meaning we can easily see how much a stack costs
- We can estimate costs by using a CloudFormation template
Productivity:
- Ability to destroy and re-create an infrastructure on the cloud on the fly
- Automated generation of Diagram for the templates
- Declarative programming, meaning no need to figure out ordering and orchestration
Separation of concerns:
- We can create as many stacks as we need, example: VPC stack, Network stack, App stack

Templates have to be uploaded in S3 and then references in CloudFormation
We can edit previous templates. We have to reupload a new version of the template to S3
Stack are identified by a name
Deleting a stack will delete every resource created

Manual way:
- Editing templates in the CloudFormation Designer
- Using the console to input parameters
Automated way:
- Editing templates in a YAML file
- Using the AWS CLI to deploy templates

Create, update or delete stacks across multiple accounts and regions with a single operation
An administration account needs to create a stack set
Trusted accounts can create, update delete stack instances from the stack set
When a stack set is updated, all the associated stack instances are updated through all accounts and regions