Introduction to AWS CloudFormation

• What is AWS CloudFormation?
  • AWS CloudFormation is a service that allows you to manage, configure, and provision your AWS infrastructure using code.
  • It enables you to define your infrastructure in a template file using either YAML or JSON format.
  • CloudFormation automates the creation of resources in the correct order with the specified configuration.
• Benefits of Using AWS CloudFormation
  • Infrastructure as Code: Ensures that resources are not created manually, allowing for better control and versioning using tools like Git.
  • Cost Management: Resources within a CloudFormation stack are tagged, making it easy to track costs and estimate expenses from templates.
  • Productivity: Enables quick creation and deletion of infrastructure, leveraging the cloud's elasticity to only pay for what you use.
  • Automated Diagram Generation: Provides visual architecture diagrams through CloudFormation Designer.
  • Declarative Programming: No need to manage the order of resource creation or orchestration, as CloudFormation handles it.
  • Separation of Concerns: Allows for multiple stacks for different applications and layers, such as network and application stacks.
  • Leverage Existing Templates: Utilize existing templates and documentation to expedite the creation of new CloudFormation templates.
• How CloudFormation Works
  • Templates must be uploaded to Amazon S3 and then referenced in CloudFormation to create a stack.
  • A CloudFormation stack is a collection of AWS resources defined in the template.
  • A new version of the template must be uploaded to update a stack, and the stack will be updated accordingly.
  • Stacks are identified by a name within an AWS region.
  • Deleting a stack removes all resources that were created by it.
• Deploying CloudFormation Templates
  • Manual Deployment: Use CloudFormation Designer or a code editor to create a template and the AWS console for parameters.
  • Automated Deployment: Edit templates as YAML files and deploy using the command-line interface (CLI) or continuous delivery tools.
• Building Blocks of CloudFormation
  • Template Format Version: Specifies the AWS template version.
  • Description: Comments about the template.
  • Resources: The core section defines the AWS resources in the template.
  • Parameters: Dynamic inputs for the template.
  • Mappings: Static variables for the template.
  • Outputs: References to the created resources.
  • Conditionals: Conditions for resource creation.
  • Template Helpers: Includes references and functions.

The training will include detailed looks at these components and practical code examples.

If your template contains custom-named IAM resources, don't create multiple stacks reusing the same template. IAM resources must be globally unique within your account.

After you execute a change, AWS CloudFormation removes all change sets that are associated with the stack because they aren't applicable to the updated stack.