Hands-On Introduction to CloudFormation - 2 hour course

This lesson introduces the first AWS CloudFormation template, which is designed to create a single EC2 instance using a specified Amazon Machine Image (AMI) and instance type within the us-east-1a availability zone. You'll learn how to upload and execute the template using AWS CloudFormation, monitor the stack creation process, and verify the instance and associated tags, setting the foundation for future lessons where the stack will be updated using additional templates.

In this lesson, we delve into updating a CloudFormation stack with a new template, which adds an EC2 instance, an Elastic IP, and a security group. We also explore the update behaviors of stack resources, understanding the potential for resource replacement and the implications for service continuity and data preservation.

In this lesson, we delve into updating an existing CloudFormation stack with a third template, focusing on a less intrusive change by adding an IAM role to an EC2 instance. This update, unlike previous ones, does not require replacing the instance, demonstrating how different types of changes can impact the resources within a stack. Additionally, we explore various CloudFormation stack options such as tagging, IAM roles, rollback configurations, and notifications, highlighting the flexibility and control CloudFormation offers over AWS resource management.

In this lesson, we learned how to delete a CloudFormation stack, which in turn removes all the resources created by that stack, such as EC2 instances, Elastic IPs, and security groups. This process simplifies cleanup in AWS by ensuring that all resources associated with a particular stack are automatically tagged and subsequently deleted when the stack is removed.

In this lesson, we begin exploring S3-focused CloudFormation templates, starting with a basic template that creates an S3 bucket. The template, derived from an Amazon-provided snippet, showcases the simplicity of defining resources in CloudFormation, leading to the creation of a uniquely named S3 bucket through the AWS Console.

In the latest lesson, we explored how to update a previously created AWS S3 bucket using CloudFormation template #5, enabling versioning and public access on the bucket without service interruption or replacing the existing resource. This illustrates the different types of update behaviors in CloudFormation, ranging from non-disruptive updates to updates requiring resource replacement.

In this lesson, the instructor demonstrated updating a CloudFormation stack with Template 6 to change the name of an S3 bucket, which requires the bucket to be replaced. The process highlighted the challenge of replacing a bucket with objects in it and concluded with the successful renaming of the bucket after ensuring it was empty, showcasing the importance of understanding resource dependencies and behaviors in CloudFormation updates.

This lesson demonstrates how to clean up AWS resources by deleting a CloudFormation stack, effectively removing all resources associated with it. It emphasizes the importance of regular cleanup during learning and experimentation within the AWS console to avoid unnecessary costs or clutter.

This lesson introduces the use of parameters in AWS CloudFormation templates to prompt for user input, allowing for template reusability across different scenarios, such as specifying open ports for security groups or choosing a VPC for EC2 instance creation. Parameters can be of various types, including string, number, and lists, and are used to customize the resources in the template, like security groups, EC2 instances, and subnets, based on user-defined criteria.

In this lesson, we explored the use of SSM (Systems Manager) parameters in AWS CloudFormation templates, particularly for securely storing and retrieving sensitive information like passwords or Amazon Machine Image (AMI) IDs. By leveraging the Parameter Store, the template dynamically fetches the latest AMI ID, ensuring that the template remains functional over time without manual updates, enhancing security and template maintainability.

This lesson explores the use of references in AWS CloudFormation templates, particularly focusing on how they can link resources and parameters, as illustrated in template seven. The lesson emphasizes good practices, such as commenting on references, and demonstrates how CloudFormation intelligently manages resource creation order based on these references.

This lesson emphasizes the advantages of using YAML over JSON for AWS CloudFormation templates, highlighting YAML's user-friendly nature and ease of interpretation. It also encourages the practice of converting JSON templates to YAML to improve familiarity with YAML formatting and structure, using AWS documentation as a reference.

In this lesson, we explored the "Depends On" attribute in AWS CloudFormation to control the creation order of resources within a stack, particularly useful when resources don't directly reference each other. Through an example, we learned how to ensure an EC2 instance is created only after a specified RDS instance, highlighting the utility of "Depends On" in scenarios where resource creation order is crucial but not inherently defined by references.

Mappings in AWS CloudFormation provide a way to define multiple key-value pairs for conditional resource deployment, such as selecting AMIs based on regions or instance types based on environments like test or production. These hardcoded mappings in the template allow for the versatile use of the same template across different settings by mapping specific configurations like AMI IDs and instance types to given conditions.

In this demo, the concept of using conditions in AWS CloudFormation templates to control resource creation is introduced, showing how resources can be conditionally created based on user inputs, such as choosing between development and production environments. The demonstration includes a hands-on exercise with Template 12, showing how conditions can determine whether additional resources like an EBS volume and mount point are created, based on the environment type selected during stack creation.