A global e-commerce company is migrating its customer-facing web application to AWS. The application experiences unpredictable traffic spikes during flash sales and seasonal events, requiring dynamic scaling. It relies on a relational database for transactional data and a caching layer for frequently accessed product information. The company wants to ensure the application remains highly available and performs optimally during these peak loads, while also optimizing costs. Which architecture best meets these requirements?
- AUtilize Amazon EC2 Auto Scaling groups with a load balancer, Amazon Aurora Multi-AZ for the database, and Amazon ElastiCache for Redis.
- BDeploy the application on a single large EC2 instance with a single Amazon RDS instance and no caching.
- CContainerize the application on Amazon ECS on Fargate, use Amazon RDS for the database, and implement client-side caching.
- DDeploy the application using AWS Lambda and Amazon DynamoDB, with API Gateway for request routing.
Show answer & explanationAnswer & explanation
Correct answer: A. Utilize Amazon EC2 Auto Scaling groups with a load balancer, Amazon Aurora Multi-AZ for the database, and Amazon ElastiCache for Redis.
EC2 Auto Scaling with a load balancer handles unpredictable traffic by dynamically adjusting capacity. Amazon Aurora Multi-AZ provides high availability and scalability for the relational database, and Amazon ElastiCache for Redis offers a highly performant, scalable caching layer, all critical for optimal performance during peak loads and cost optimization by scaling down during low periods.
Why the other options are wrong
- B. A single EC2 instance and RDS instance without caching is highly susceptible to traffic spikes and offers no high availability, failing to meet the requirements.
- C. ECS on Fargate provides container scalability, and RDS is a relational database. However, 'client-side caching' is generally insufficient and less efficient than a distributed server-side caching solution like ElastiCache for frequently accessed product information, especially for a high-traffic e-commerce site.
- D. While serverless (Lambda, DynamoDB) offers high scalability, migrating a 'customer-facing web application' to a purely serverless architecture might involve significant re-architecture not implied by the question, and DynamoDB is a NoSQL database, whereas the requirement specifies a 'relational database' for transactional data.
Scalable Web Application Architecture
A scalable web application architecture on AWS typically involves using auto-scaling compute (EC2 Auto Scaling, ECS/Fargate), a highly available and scalable database (Aurora Multi-AZ), and a distributed caching layer (ElastiCache) to handle variable traffic loads and ensure optimal performance and cost efficiency.
- Decouples components for independent scaling
- Utilizes managed services for operational efficiency
- Employs caching to reduce database load and improve response times
- Designed for high availability and fault tolerance
Memory trick: Auto-scale, Aurora, ElastiCache: The Triple-A for E-commerce.