The customer requires a disaster recovery (DR) solution with failover and fallback capabilities between their on-premises data center and the public cloud. Pure Storage Cloud Block Store (CBS) is a software-defined version of the Purity//FA operating environment that runs natively in AWS and Azure. It can act as a replication target for an on-premise FlashArray. Using asynchronous snapshot replication, customers can replicate data to CBS, enabling the cloud to serve as a fully functional DR site. This configuration directly supports failing over operations to the cloud and subsequently failing back to the on-premises array once it is restored.

B. Purity//FA CloudSnap periodic offload of snapshots to AWS: CloudSnap is designed for cost-effective, long-term data retention and archival by sending snapshots to cloud object storage (e.g., S3), not for rapid DR with low RTO.

C. ActiveCluster FC replication between a FlashArray on site and Evergreen//One: ActiveCluster is a synchronous, active-active replication solution for business continuity (zero RPO/RTO), not typically used for long-distance on-prem-to-cloud DR. Also, FC is not the transport for cloud replication.

1. Pure Storage Official Documentation, "Disaster Recovery to the Cloud with Pure Cloud Block Store" Solution Brief.

Reference: Page 2, "Solution Overview" section states, "Pure Cloud Block Store™ enables disaster recovery (DR) to the cloud by providing seamless data mobility between on-premises FlashArray™ devices and the public cloud... You can use asynchronous replication to fail over to the cloud and fail back to on-premises when ready." This directly supports using snapshot replication between FlashArray and CBS for DR.

2. Pure Storage Official Documentation, "Purity//FA User Guide".

Reference: In the section on "Protection," CloudSnap is described as a feature to "offload snapshots to a cloud namespace for archival purposes." This differentiates its use case from the active DR scenario required by the question.

3. Pure Storage Official Documentation, "ActiveCluster" White Paper.

Reference: The "Overview" section describes ActiveCluster as a "multi-site active-active stretch cluster solution that provides synchronous replication." This confirms it is for business continuity with zero recovery time, a different use case than DR to the cloud, and it typically uses Fibre Channel or IP for shorter, metro distances.