Skip to content
Learni
View all tutorials
Cloud & DevOps

How to Deploy an AWS CloudFormation Stack in 2026

12 minBEGINNER
AWSIaCCloudFormation
Lire en français

Introduction

AWS CloudFormation lets you describe your infrastructure as code. Instead of clicking in the console, you define resources in a YAML or JSON file. This makes your deployments reproducible, versionable, and secure. In 2026, this IaC approach is essential for any serious AWS project. This tutorial walks you through creating a simple stack containing an S3 bucket, from writing the template to deploying it via CLI.

Prerequisites

  • AWS account with sufficient IAM permissions
  • AWS CLI installed and configured (aws configure)
  • Basic knowledge of YAML
  • Node.js not required for this beginner tutorial

Basic CloudFormation Template

s3-bucket.yaml
AWSTemplateFormatVersion: '2010-09-09'
Description: 'Bucket S3 simple pour débutants'
Resources:
  MonBucketS3:
    Type: AWS::S3::Bucket
    Properties:
      BucketName: mon-bucket-tutoriel-2026
      AccessControl: Private
      Tags:
        - Key: Environment
          Value: Tutorial

This minimal template creates a private S3 bucket. The name must be globally unique. Tags help with identification and billing.

Adding Parameters

s3-bucket-params.yaml
AWSTemplateFormatVersion: '2010-09-09'
Description: 'Bucket S3 avec paramètres'
Parameters:
  BucketNameParam:
    Type: String
    Default: mon-bucket-tutoriel-2026
    Description: Nom unique du bucket S3
Resources:
  MonBucketS3:
    Type: AWS::S3::Bucket
    Properties:
      BucketName: !Ref BucketNameParam
      AccessControl: Private

Parameters make the template reusable. !Ref references the value provided at deployment time.

Template Validation

terminal
aws cloudformation validate-template --template-body file://s3-bucket-params.yaml

This command checks syntax and common errors before deployment. It prevents costly failures.

Deploying the Stack

terminal
aws cloudformation create-stack \
  --stack-name TutorielS3 \
  --template-body file://s3-bucket-params.yaml \
  --parameters ParameterKey=BucketNameParam,ParameterValue=mon-bucket-unique-2026

create-stack starts resource creation. The stack name must be unique within the region.

Update and Delete

terminal
aws cloudformation update-stack --stack-name TutorielS3 --template-body file://s3-bucket-params.yaml --parameters ParameterKey=BucketNameParam,ParameterValue=mon-bucket-unique-2026

aws cloudformation delete-stack --stack-name TutorielS3

update-stack applies changes. delete-stack removes all resources created by the stack.

Best Practices

  • Always use parameters for variable values
  • Add tags systematically for cost tracking
  • Version your templates in Git
  • Test with validate-template before every deployment
  • Prefer small, focused stacks over monolithic ones

Common Errors to Avoid

  • Non-unique bucket name (409 error)
  • Forgetting to configure the AWS CLI region
  • Not using --capabilities for IAM resources
  • Manually deleting resources managed by CloudFormation

Going Further

Discover our advanced AWS and IaC courses: https://learni-group.com/formations