Q45 — AWS SAA-C03 Ch.5
Question 45 of 65 | ← Chapter 5
Q345. A company hosts a multi-tier web application on Amazon Linux Amazon EC2instances behind an Application Load Balancer. The instances run in an Auto Scaling group across multiple Availability Zones. The company observes that the Auto Scaling group launches more On-Demand Instances when the application's end users access high volumes of static web content. The company wants to optimize cost. What should a solutions architect do to redesign the application MOST cost-effectively?
- A. Update the Auto Scaling group to use Reserved Instances instead of On-Demand Instances.
- B. Update the Auto Scaling group to scale by launching Spot Instances instead of On-Demand Instances.
- C. Create an Amazon CloudFront distribution to host the static web contents from an Amazon S3 bucket. ✓
- D. Create an AWS Lambda function behind an Amazon API Gateway API to host the static website contents.
Correct Answer: C. Create an Amazon CloudFront distribution to host the static web contents from an Amazon S3 bucket.
Explanation
Since the company observes that the Auto Scaling group launches more On-Demand Instances when the application's end users access high volumes of static web content, using a Content Delivery Network (CDN) to cache and serve the static content can greatly reduce the load on the EC2 instances. Amazon CloudFront is an AWS service that provides a global CDN with low-latency, high-speed data transfer from a secure and reliable network. The company can create an Amazon CloudFront distribution to host the static web contents from an Amazon S3 bucket. This will help in reducing the total number of requests that are sent to the origin server, which in turn reduces the need for additional compute resources in the Auto Scaling group. This reduction in compute resources results in lower costs. Option A would not be effective since Reserved Instances require upfront payment and are billed hourly irrespective of whether they are used or not.Option B may lead to cost optimization but comes at the risk of Spot instance termination. Option D is not suited for hosting static web content since it involves additional overheads, including API Gateway and Lambda usage charges.