AWS Certified Solutions Architect – Associate (SAA-C03) — Question 440

A company runs a website that uses a content management system (CMS) on Amazon EC2. The CMS runs on a single EC2 instance and uses an Amazon Aurora MySQL Multi-AZ DB instance for the data tier. Website images are stored on an Amazon Elastic Block Store (Amazon EBS) volume that is mounted inside the EC2 instance.

Which combination of actions should a solutions architect take to improve the performance and resilience of the website? (Choose two.)

Answer options

• A. Move the website images into an Amazon S3 bucket that is mounted on every EC2 instance
• B. Share the website images by using an NFS share from the primary EC2 instance. Mount this share on the other EC2 instances.
• C. Move the website images onto an Amazon Elastic File System (Amazon EFS) file system that is mounted on every EC2 instance.
• D. Create an Amazon Machine Image (AMI) from the existing EC2 instance. Use the AMI to provision new instances behind an Application Load Balancer as part of an Auto Scaling group. Configure the Auto Scaling group to maintain a minimum of two instances. Configure an accelerator in AWS Global Accelerator for the website
• E. Create an Amazon Machine Image (AMI) from the existing EC2 instance. Use the AMI to provision new instances behind an Application Load Balancer as part of an Auto Scaling group. Configure the Auto Scaling group to maintain a minimum of two instances. Configure an Amazon CloudFront distribution for the website.

Correct answer: C, E

Explanation

To make the website resilient and performant, the single EC2 instance must be replaced with an Auto Scaling group behind an Application Load Balancer, combined with Amazon CloudFront to cache and deliver content globally with low latency. Since multiple EC2 instances now need shared, simultaneous access to the website images, Amazon Elastic File System (Amazon EFS) is the correct choice as it supports concurrent read/write access and high availability. Using S3 as a mounted drive is not natively supported or performant for this use case, and an NFS share hosted on a single EC2 instance creates a single point of failure.