Q67 — AWS SAA-C03 Ch.16

Question 67 of 100 | ← Chapter 16

Q1267. A company is building a new web application on AWS. The application needs to consume files from a legacy on-premises application that runs a batch process and outputs approximately 1 GB of data every night to an NFS file mount.A solutions architect needs to design a storage solution that requires minimal changes to the legacy application and keeps costs low.Which solution will meet these requirements MOST cost-effectively?

Correct Answer: D. Deploy an Amazon S3 File Gateway on premises. Point the legacy application to the File Gateway.Configure the web application to retrieve the files from the S3 bucket that the File Gateway uses.

Explanation

The most cost-effective solution that requires minimal changes to the legacy application while providing seamless access to files for the AWS-based web application is:Correct Answer: D. Deploy an Amazon S3 File Gateway on premises. Point the legacy application to the File Gateway. Configure the web application to retrieve the files from the S3 bucket that the File Gateway uses.Why Option D is Best:Minimal Changes to Legacy Application:The legacy application continues to use NFS mounts (as it does today) but points to the S3 File Gateway instead of a local NFS server.No need to rewrite the application to use S3 APIs directly.Cost-Effective Storage:Amazon S3 is used for storage, which is cheaper than maintaining on-premises storage or using AWS Outposts/Storage Gateway Volume Gateway (which require additional compute/storage overhead). No need for expensive hardware--the File Gateway can run on a VM or low-cost server.Seamless Integration with AWS Web Application:The web application can directly access files in S3 (no gateway needed for retrieval). Files are automatically synchronized between the on-premises File Gateway and S3.Scalability & Reliability:S3 provides high durability (99.999999999%) and scalability without manual intervention.Why Other Options Are Less Cost-Effective or Suitable:A. Deploy an Outpost in AWS Outposts to the on-premises location where the legacy application is stored. Configure the legacy application and the web application to store and retrieve the files in Amazon S3 on the Outpost.Extremely expensive (Outposts require AWS hardware installed on-premises, with high costs for compute and storage).Overkill for a simple file transfer use case.Not cost-effective for small data volumes (1 GB/night).B. Deploy an AWS Storage Gateway Volume Gateway on premises. Point the legacy application to the Volume Gateway. Configure the web application to use the Amazon S3 bucket that the Volume Gateway uses.More complex than needed: Volume Gateway is designed for block storage (iSCSI), not NFS file shares. Legacy application would need to use iSCSI instead of NFS, requiring more changes than the File Gateway.Higher cost than S3 File Gateway (due to cached volumes/storage requirements). C. Deploy an Amazon S3 interface endpoint on AWS. Reconfigure the legacy application to store the files directly on an Amazon S3 endpoint. Configure the web application to retrieve the files from Amazon S3. Requires modifying the legacy application to use S3 APIs (e.g., AWS SDK or REST calls) instead of NFS. Not minimal changes--could involve significant development effort.Not ideal if the legacy system is rigid or undocumented.Cost Comparison (Estimated for 1 GB/night over 1 Year)OptionCost EstimateKey Trade-offsD. S3 File Gateway~300+/year (iSCSI storage + gateway VM) More expensive, requires app changes A. AWS Outposts45/year (S3) + Dev Costs Requires app rewritesConclusionOption D (S3 File Gateway) is the most cost-effective and least disruptive solution because:Legacy app keeps using NFS (no rewrites).Files are stored in low-cost S3.Web app accesses files directly from S3.No expensive hardware or complex configurations.Final Answer: D