Deploying a CloudFormation Stack

Modern AWS infrastructure is expected to be reproducible, version-controlled,
reviewable, and deployable through automation. AWS CloudFormation sits at the
center of that operational model.

A CloudFormation stack is the deployed instance of an infrastructure template.
The template defines the desired state of AWS resources, while the stack
represents the actual running infrastructure created from that definition.

Core Concept:
The template is the blueprint. The stack is the deployed infrastructure.

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Understanding What Gets Deployed

Every deployment begins with a CloudFormation template. That template may be:

• Written directly in YAML or JSON
• Generated by AWS CDK
• Expanded through AWS SAM transforms
• Produced through automation pipelines

Tool	What You Write	What CloudFormation Receives
AWS CDK	TypeScript / Python / Java	Synthesized CloudFormation Template
CloudFormation	YAML / JSON	Same Template
AWS SAM	Serverless Template	Expanded CloudFormation Template

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Deploying Infrastructure Using AWS CDK

AWS CDK allows infrastructure to be written using real programming languages
instead of verbose YAML templates.

Step 1: Initialize the CDK Application

npm install -g aws-cdk

mkdir ecs-demo
cd ecs-demo

cdk init app --language typescript

Step 2: Define the Stack

import * as cdk from 'aws-cdk-lib';
import * as ecs from 'aws-cdk-lib/aws-ecs';
import * as ec2 from 'aws-cdk-lib/aws-ec2';
import * as ecs_patterns from 'aws-cdk-lib/aws-ecs-patterns';

export class EcsDemoStack extends cdk.Stack {

  constructor(scope, id) {
    super(scope, id);

    const vpc = new ec2.Vpc(this, 'AppVpc');

    const cluster = new ecs.Cluster(this, 'AppCluster', {
      vpc
    });

    new ecs_patterns.ApplicationLoadBalancedFargateService(
      this,
      'AppService',
      {
        cluster,
        taskImageOptions: {
          image: ecs.ContainerImage.fromRegistry('nginx')
        }
      }
    );
  }
}

Step 3: Bootstrap the Environment

cdk bootstrap

This creates the bootstrap stack:

CDKToolkit

Step 4: Synthesize the Template

cdk synth

CDK converts application constructs into a full CloudFormation template.

Step 5: Deploy the Stack

cdk deploy

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What Happens During Deployment

1. CloudFormation validates the template
2. Dependencies between resources are resolved
3. Resources are provisioned in parallel
4. Stack events stream continuously
5. Rollback occurs automatically on failure

Monitoring Stack Events

aws cloudformation describe-stack-events \
  --stack-name EcsDemoStack

---

Rollback Behavior

If resource creation fails midway, CloudFormation automatically rolls back
the deployment.

For debugging large deployments:

cdk deploy --no-rollback

---

Deploying Using the AWS CLI

Create a Stack

aws cloudformation create-stack \
  --stack-name networking-stack \
  --template-body file://vpc.yaml \
  --capabilities CAPABILITY_IAM

Update a Stack

aws cloudformation update-stack \
  --stack-name networking-stack \
  --template-body file://vpc.yaml

Delete a Stack

aws cloudformation delete-stack \
  --stack-name networking-stack

---

Deploying Through CI/CD Pipelines

Using Change Sets

aws cloudformation create-change-set \
  --stack-name production-stack \
  --change-set-name v2-update \
  --template-body file://template.yaml

Change sets preview infrastructure modifications before execution.

---

Drift Detection

aws cloudformation detect-stack-drift \
  --stack-name production-stack

Drift detection identifies infrastructure modified outside CloudFormation.

---

Termination Protection

aws cloudformation update-termination-protection \
  --stack-name production-stack \
  --enable-termination-protection

Termination protection prevents accidental deletion of production
infrastructure.

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Final Thoughts

CloudFormation deployment is fundamentally about managing infrastructure as a
deterministic and reproducible system.

Whether infrastructure is deployed through:

• AWS CDK
• Raw CloudFormation
• AWS SAM
• AWS CLI
• CI/CD Pipelines

the underlying CloudFormation engine remains the same.

Understanding dependency resolution, rollback handling, resource
stabilization, and stack lifecycle management is what separates
basic AWS usage from production-grade infrastructure engineering.