AWS Certified Solutions Architect – Associate (SAA-C03) — Question 539

A company runs multiple Amazon EC2 Linux instances in a VPC across two Availability Zones. The instances host applications that use a hierarchical directory structure. The applications need to read and write rapidly and concurrently to shared storage.

What should a solutions architect do to meet these requirements?

Answer options

• A. Create an Amazon S3 bucket. Allow access from all the EC2 instances in the VPC.
• B. Create an Amazon Elastic File System (Amazon EFS) file system. Mount the EFS file system from each EC2 instance.
• C. Create a file system on a Provisioned IOPS SSD (io2) Amazon Elastic Block Store (Amazon EBS) volume. Attach the EBS volume to all the EC2 instances.
• D. Create file systems on Amazon Elastic Block Store (Amazon EBS) volumes that are attached to each EC2 instance. Synchronize the EBS volumes across the different EC2 instances.

Correct answer: B

Explanation

Amazon Elastic File System (Amazon EFS) is designed to provide serverless, fully managed, concurrent shared file storage for Amazon EC2 Linux instances across multiple Availability Zones. Amazon S3 (Option A) is object storage rather than a traditional hierarchical file system, making it less suitable for applications requiring rapid, native directory-level file operations. Amazon EBS volumes (Options C and D) cannot be natively shared concurrently across multiple Availability Zones with the high performance and low complexity offered by EFS.