AWS CloudFormation – Infrastructure as Code für AWS 2025

CloudFormation vs. Terraform

Erste CloudFormation Stack

# stack-ec2.yaml
AWSTemplateFormatVersion: '2010-09-09'
Description: 'Einfache EC2-Instanz mit Security Group'

Parameters:
  InstanceType:
    Type: String
    Default: t3.small
    AllowedValues: [t3.micro, t3.small, t3.medium]
  KeyName:
    Type: AWS::EC2::KeyPair::KeyName
    Description: SSH Key Pair

Mappings:
  RegionAMI:
    eu-central-1:
      Ubuntu2404: ami-0a628e1e89aaedf80

Resources:
  WebSecurityGroup:
    Type: AWS::EC2::SecurityGroup
    Properties:
      GroupDescription: Web Server Security Group
      SecurityGroupIngress:
        - IpProtocol: tcp
          FromPort: 80
          ToPort: 80
          CidrIp: 0.0.0.0/0
        - IpProtocol: tcp
          FromPort: 443
          ToPort: 443
          CidrIp: 0.0.0.0/0
        - IpProtocol: tcp
          FromPort: 22
          ToPort: 22
          CidrIp: 0.0.0.0/0

  WebServer:
    Type: AWS::EC2::Instance
    Properties:
      InstanceType: !Ref InstanceType
      ImageId: !FindInMap [RegionAMI, !Ref AWS::Region, Ubuntu2404]
      KeyName: !Ref KeyName
      SecurityGroupIds:
        - !Ref WebSecurityGroup
      UserData:
        Fn::Base64: !Sub |
          #!/bin/bash
          apt update && apt install -y nginx
          systemctl enable --now nginx
      Tags:
        - Key: Name
          Value: !Sub '${AWS::StackName}-web-server'

Outputs:
  PublicIP:
    Value: !GetAtt WebServer.PublicIp
    Description: Public IP Address
  InstanceId:
    Value: !Ref WebServer

# Stack deployen
aws cloudformation deploy     --stack-name firma-web-server     --template-file stack-ec2.yaml     --parameter-overrides InstanceType=t3.small KeyName=mein-key     --capabilities CAPABILITY_IAM

# Stack-Status
aws cloudformation describe-stacks     --stack-name firma-web-server     --query 'Stacks[0].{Status:StackStatus,Outputs:Outputs}'

# Outputs abrufen
aws cloudformation describe-stacks     --stack-name firma-web-server     --query 'Stacks[0].Outputs'

Nested Stacks

# main-stack.yaml
Resources:
  VPCStack:
    Type: AWS::CloudFormation::Stack
    Properties:
      TemplateURL: https://s3.amazonaws.com/meine-templates/vpc-stack.yaml

  EC2Stack:
    Type: AWS::CloudFormation::Stack
    DependsOn: VPCStack
    Properties:
      TemplateURL: https://s3.amazonaws.com/meine-templates/ec2-stack.yaml
      Parameters:
        VpcId: !GetAtt VPCStack.Outputs.VpcId

Stack aktualisieren und Rollback

# Änderungssatz (Change Set) erstellen vor Update
aws cloudformation create-change-set     --stack-name firma-web-server     --change-set-name meine-aenderung     --template-file stack-ec2.yaml     --parameter-overrides InstanceType=t3.medium

# Change Set anzeigen
aws cloudformation describe-change-set     --stack-name firma-web-server     --change-set-name meine-aenderung

# Change Set ausführen
aws cloudformation execute-change-set     --stack-name firma-web-server     --change-set-name meine-aenderung

# Stack löschen
aws cloudformation delete-stack --stack-name firma-web-server

FAQ

Wann CloudFormation, wann Terraform für AWS?
CloudFormation: wenn ausschließlich AWS, kein State-Management-Aufwand. Terraform: wenn Multi-Cloud oder bestehender Terraform-Stack vorhanden.

Fazit

CloudFormation ermöglicht reproduzierbare AWS-Infrastruktur. Templates in Git versioniert machen Deployments auditierbar.

AWS CloudFormation und IaC für KMU in Heidelberg, Mannheim und der Rhein-Neckar-Region. Anfragen.