An urban planning firm maintains a high-capacity on-premises file server that delivers project documents via an iSCSI-attached storage array. The storage system contains over 400 TB of mixed file types, including CAD drawings and legal records. To improve business continuity, the firm wants to implement a disaster recovery strategy. The solution must allow local teams uninterrupted access to files with minimal latency and must require the fewest possible modifications to their existing setup. What approach should the firm adopt to meet these needs with the least operational disruption?