Hitachi ShadowImage

Hitachi ShadowImage is a disaster recovery and data replication solution designed for enterprise-level storage environments. It creates exact, continuous copies of data volumes on a secondary storage system in real-time. This allows businesses to maintain a highly available backup that can be mounted and used immediately if the primary system fails.

Unlike traditional backups that take point-in-time snapshots on a schedule, ShadowImage provides synchronous, continuous data protection. It mirrors every single write operation to a secondary volume instantly, ensuring the backup is identical to the primary data up to the millisecond. This allows for rapid failover and near-zero data loss (an RPO of zero) in the event of a catastrophic hardware failure.

Hitachi ShadowImage is primarily a software feature that runs directly on Hitachi Vantara enterprise storage arrays, such as the VSP (Virtual Storage Platform) series. The replication process occurs internally within the storage controllers rather than consuming host server resources. This ensures that the data mirroring process does not impact the performance of your application servers.

Yes, one of the primary benefits of ShadowImage is the ability to split the primary and secondary volumes. Once split, the secondary volume is an independent, exact replica of the data that can be mounted to a test server. This allows administrators to run disaster recovery tests or perform database analytics without risking the integrity of the production data.