Book Image

Mastering AWS CloudFormation - Second Edition

By : Karen Tovmasyan
Book Image

Mastering AWS CloudFormation - Second Edition

By: Karen Tovmasyan

Overview of this book

The advent of DevOps and the cloud revolution has compelled software engineers and operations teams to rethink how to manage complex infrastructures and build resilient solutions. With this AWS book, you’ll find out how you can use Infrastructure as Code (IaC) to simplify infrastructure operations and manage the modern cloud with AWS CloudFormation. This guide covers AWS CloudFormation comprehensively, from template structures to developing complex and reusable infrastructure stacks. It takes you through template validation, stack deployment, and handling deployment failures. It also demonstrates the use of AWS CodeBuild and CodePipeline for automating resource delivery and implementing continuous integration and continuous delivery (CI/CD) practices. As you advance, you’ll learn how to modularize and unify your template on the fly using macros or by fixating the version using modules. You’ll create resources outside of AWS with custom resources and catalog them with the CloudFormation registry. Finally, you’ll improve the way you manage the modern cloud environment on AWS by extending CloudFormation through the AWS serverless application model (SAM) and the AWS cloud development kit (CDK). By the end of this book, you’ll have mastered key AWS CloudFormation concepts and will be able to extend its capabilities for developing and deploying your own infrastructure.
Table of Contents (19 chapters)
Free Chapter
1
Part 1: CloudFormation Internals
4
Part 2: Provisioning and Deployment at Scale
9
Part 3: Extending CloudFormation

Using cfn-signal to inform CloudFormation about resource readiness

CloudFormation reports resource readiness as soon as it retrieves a response from AWS’s API that the resource is created. By this, we understand that if we create a Relational Database Service (RDS) instance and CloudFormation tells us that it’s created, then we can connect to it right away.

While this is applicable for most of the managed services at AWS, it doesn’t work on services that we run based on EC2. You see, CloudFormation is not aware that EC2 has a job to run and reports Done once the instance is in a Running state.

For small development environments, this might be fine, but imagine running a web application on an AutoScaling group. While the instance takes time to install packages and start services, AutoScaling reports that the instance is unhealthy and terminates it. A new one starts, time passes, and then it gets terminated. The worst thing here is that CloudFormation will...