AWS Certified Solutions Architect – Professional (SAP-C02) — Question 498

An entertainment company hosts a ticketing service on a fleet of Linux Amazon EC2 instances that are in an Auto Scaling group. The ticketing service uses a pricing file. The pricing file is stored in an Amazon S3 bucket that has S3 Standard storage. A central pricing solution that is hosted by a third party updates the pricing file.

The pricing file is updated every 1-15 minutes and has several thousand line items. The pricing file is downloaded to each EC2 instance when the instance launches.

The EC2 instances occasionally use outdated pricing information that can result in incorrect charges for customers.

Which solution will resolve this problem MOST cost-effectively?

Answer options

• A. Create an AWS Lambda function to update an Amazon DynamoDB table with new prices each time the pricing file is updated. Update the ticketing service to use DynramoDB to look up pricing
• B. Create an AWS Lambda function to update an Amazon Elastic File System (Amazon EFS) file share with the pricing file each time the file is updated. Update the ticketing service to use Amazon EFS to access the pricing file.
• C. Load Mountpoint for Amazon S3 onto the AMI of the EC2 instances. Configure Mountpoint for Amazon S3 to mount the S3 bucket that contains the pricing file. Update the ticketing service to point to the mount point and path to access the $3 object,
• D. Create an Amazon Elastic Block Store (Amazon EBS) volume. Use EBS Multi-Attach to attach the volume to every EC2 instance. When a new EC2 instance launches, configure the new instance to update the pricing file on the EBS volume. Update the ticketing service to point to the new local source.

Correct answer: C

Explanation

Mountpoint for Amazon S3 allows EC2 instances to access objects in S3 directly as a local file system, ensuring they always read the most up-to-date pricing file without incurring the overhead of managing Lambda functions, DynamoDB tables, or EFS. This approach is highly cost-effective because S3 Standard storage and API requests are cheap, and Mountpoint is an open-source tool with no licensing or extra infrastructure costs. Other options like DynamoDB, EFS, or EBS Multi-Attach introduce unnecessary architectural complexity and higher storage/compute costs.