AWS Certified Solutions Architect – Associate (SAA-C02) — Question 477

A company is running a media store across multiple Amazon EC2 instances distributed across multiple Availability Zones in a single VPC. The company wants a high-performing solution to share data between all the EC2 instances, and prefers to keep the data within the VPC only.
What should a solutions architect recommend?

Answer options

• A. Create an Amazon S3 bucket and call the service APIs from each instance's application.
• B. Create an Amazon S3 bucket and configure all instances to access it as a mounted volume.
• C. Configure an Amazon Elastic Block Store (Amazon EBS) volume and mount it across all instances.
• D. Configure an Amazon Elastic File System (Amazon EFS) file system and mount it across all instances.

Correct answer: D

Explanation

Amazon Elastic File System (Amazon EFS) is a managed file storage service that supports the Network File System (NFS) protocol, allowing it to be mounted concurrently by multiple Amazon EC2 instances across multiple Availability Zones in a single VPC. Amazon EBS volumes (excluding Multi-Attach, which is restricted to a single AZ) cannot be mounted across different AZs. Amazon S3 is an object storage service rather than a high-performance, POSIX-compliant shared file system, making Amazon EFS the ideal choice for this scenario.