AWS Certified Solutions Architect – Associate (SAA-C03) — Question 899

A company needs to design a resilient web application to process customer orders. The web application must automatically handle increases in web traffic and application usage without affecting the customer experience or losing customer orders.

Which solution will meet these requirements?

Answer options

• A. Use a NAT gateway to manage web traffic. Use Amazon EC2 Auto Scaling groups to receive, process, and store processed customer orders. Use an AWS Lambda function to capture and store unprocessed orders.
• B. Use a Network Load Balancer (NLB) to manage web traffic. Use an Application Load Balancer to receive customer orders from the NLUse Amazon Redshift with a Multi-AZ deployment to store unprocessed and processed customer orders.
• C. Use a Gateway Load Balancer (GWLB) to manage web traffic. Use Amazon Elastic Container Service (Amazon ECS) to receive and process customer orders. Use the GWLB to capture and store unprocessed orders. Use Amazon DynamoDB to store processed customer orders.
• D. Use an Application Load Balancer to manage web traffic. Use Amazon EC2 Auto Scaling groups to receive and process customer orders. Use Amazon Simple Queue Service (Amazon SQS) to store unprocessed orders. Use Amazon RDS with a Multi-AZ deployment to store processed customer orders.

Correct answer: D

Explanation

Option D is correct because an Application Load Balancer and EC2 Auto Scaling provide elastic scalability for HTTP/HTTPS traffic, while Amazon SQS acts as a buffer to decouple components and prevent message loss during high traffic. Additionally, a Multi-AZ Amazon RDS deployment ensures high availability and durability for transactional order data. Other options are incorrect because NAT gateways and GWLBs are not designed for standard web application load balancing, and Amazon Redshift is an OLAP data warehouse rather than a transactional database suited for order processing.