Volume Gateway is a service that provides cloud-backed iSCSI block storage volumes for on-premises applications. It manages your on-premises data in Amazon S3 and operates in two modes: cache mode, where primary data is stored in Amazon S3 with frequently accessed data cached locally, and stored mode, where primary data is stored locally while being backed up to Amazon S3.

In cached Volume Gateway mode, your primary data is stored in Amazon S3, while frequently accessed data is retained locally in the cache. This setup allows for low latency access to the data that is most often used, improving performance for on-premises applications.

Volume Gateway allows you to take point-in-time copies of your volumes using AWS Backup. These copies are stored as Amazon EBS snapshots in AWS, enabling space-efficient versioned backups for data protection, recovery, migration, and other copy data needs.