Hitachi TrueCopy

TrueCopy synchronous mode (TrueCopy/S) writes data to both the primary and secondary Hitachi storage arrays before acknowledging the write to the host, ensuring zero data loss but requiring the arrays to be within a limited distance for acceptable latency. Asynchronous mode writes to the primary first, then replicates to the secondary with a small, configurable RPO, allowing replication over much longer distances. The choice depends on the workload's tolerance for latency versus data loss.

TrueCopy is supported across Hitachi VSP (Virtual Storage Platform) enterprise and mid-range arrays, including the VSP G-series, VSP F-series (all-flash), and the newer VSP One Block family. It is a separately licensed storage feature. TrueCopy has been a core differentiator for Hitachi storage since the early generations of the HDS (Hitachi Data Systems) product line.

For synchronous TrueCopy, the practical distance is typically limited to approximately 100 km (about 60 miles) because the round-trip fiber optic latency at greater distances degrades application write performance unacceptably. Beyond that range, Hitachi recommends Universal Replicator (UR), its asynchronous replication technology, which has no meaningful distance limitation. The exact distance depends on the application's latency sensitivity and the fiber link quality.

Yes, Zerto can integrate with Hitachi TrueCopy by leveraging the storage-level replication as the data transport while providing orchestration, automated failover, and non-disruptive DR testing through its Virtual Manager. This approach offloads replication to the storage array for efficiency while Zerto manages recovery at the VM level. The combination is used in environments where TrueCopy is already deployed and organizations want Zerto's orchestration capabilities layered on top.