Answer: Deploy an AWS Storage Gateway volume gateway that is configured with cached volumes.

## Explanation This question is about migrating iSCSI storage servers to AWS while maintaining low-latency access to frequently used data with minimal infrastructure changes. Let's analyze each option: **A. Deploy an Amazon S3 File Gateway.** - This is incorrect because S3 File Gateway provides file-based access (NFS/SMB) to Amazon S3, not block storage access. - iSCSI is a block storage protocol, so this wouldn't be compatible with existing iSCSI applications. **B. Deploy Amazon Elastic Block Store (Amazon EBS) storage with backups to Amazon S3.** - This is incorrect because EBS is a cloud-native block storage service that requires applications to be migrated to AWS. - This would require significant infrastructure changes, not "minimal number of infrastructure changes." **C. Deploy an AWS Storage Gateway volume gateway that is configured with stored volumes.** - This is incorrect for this specific requirement. - Stored volumes keep the entire dataset locally and asynchronously back up to AWS. - This doesn't reduce on-premises storage dependency significantly since all data is still stored locally. **D. Deploy an AWS Storage Gateway volume gateway that is configured with cached volumes.** - **CORRECT ANSWER** - Cached volumes store only frequently accessed data locally while keeping the entire dataset in Amazon S3. - This provides low-latency access to frequently used data (cached locally). - Reduces dependency on on-premises servers by moving the primary data store to AWS. - Requires minimal infrastructure changes - just deploy the Storage Gateway appliance. - Maintains iSCSI compatibility for existing applications. **Key AWS Services:** - **AWS Storage Gateway**: Hybrid cloud storage service that connects on-premises environments with AWS cloud storage. - **Volume Gateway**: Provides iSCSI block storage access to cloud storage. - **Cached Volumes**: Store primary data in Amazon S3, cache frequently accessed data locally. - **Stored Volumes**: Store primary data locally, asynchronously back up to AWS. **Why this meets the requirements:** 1. **Low-latency access to frequently used data**: Frequently accessed data is cached locally. 2. **Reduce dependency on on-premises servers**: Primary data storage moves to Amazon S3. 3. **Minimal infrastructure changes**: Just deploy the Storage Gateway appliance; existing iSCSI applications continue to work unchanged.

Author: LeetQuiz Editorial Team