AWS Certified Solutions Architect – Professional — Question 771

A company is running a traditional web application on Amazon EC2 instances. The company needs to refactor the application as microservices that run on containers. Separate versions of the application exist in two distinct environments: production and testing. Load for the application is variable, but the minimum load and the maximum load are known. A solutions architect needs to design the updated application with a serverless architecture that minimizes operational complexity.

Which solution will meet these requirements MOST cost-effectively?

Answer options

• A. Upload the container images to AWS Lambda as functions. Configure a concurrency limit for the associated Lambda functions to handle the expected peak load. Configure two separate Lambda integrations within Amazon API Gateway: one for production and one for testing.
• B. Upload the container images to Amazon Elastic Container Registry (Amazon ECR). Configure two auto scaled Amazon Elastic Container Service (Amazon ECS) clusters with the Fargate launch type to handle the expected load. Deploy tasks from the ECR images. Configure two separate Application Load Balancers to direct traffic to the ECS clusters.
• C. Upload the container images to Amazon Elastic Container Registry (Amazon ECR). Configure two auto scaled Amazon Elastic Kubernetes Service (Amazon EKS) clusters with the Fargate launch type to handle the expected load. Deploy tasks from the ECR images. Configure two separate Application Load Balancers to direct traffic to the EKS clusters.
• D. Upload the container images to AWS Elastic Beanstalk. In Elastic Beanstalk, create separate environments and deployments for production and testing. Configure two separate Application Load Balancers to direct traffic to the Elastic Beanstalk deployments.

Correct answer: B

Explanation

Amazon ECS with AWS Fargate provides a fully managed, serverless container execution environment that minimizes operational complexity and aligns perfectly with the known variable load. Amazon EKS (Option C) introduces significantly more management overhead and cluster setup complexity compared to ECS. AWS Lambda (Option A) is less cost-effective for continuous web application workloads with defined minimum and maximum loads, while AWS Elastic Beanstalk (Option D) is not a serverless container solution.