InfoWorld review: Data deduplication appliances
Data deduplication appliances from FalconStor, NetApp, and Spectra Logic provide excellent data reduction for production storage, disk-based backups, and virtual tape
I ran Backup Exec agents on four Windows Server 2008 R2 virtual machines running on Microsoft Hyper-V as well as a physical Windows Server 2008 R2 server. After the initial backups, the deduplication engine did an excellent job of detecting redundant data in each subsequent backup. I even tried to fool it by renaming groups of folders without changing the contents. In each case, the deduplication engine recognized the data and greatly reduced my backup size and replication footprint. In my test configuration, deduplication was done post-backup, but I could have easily run it in parallel with the backup. There is a slight performance penalty to deduping in real time, so for most users, post-processing is the way to go.
When a backup is made to one of the virtual tape drives, the data is written to the virtual tape in the same format as if it were a physical tape. This allows a copy to be saved and deduped on the nTier appliance and then streamed to a physical tape for off-site archival. One big advantage to using VTL is that IT staff already using physical tape drives and libraries don't have to learn a new backup system. They continue to use the same backup programs and schedules they are used to. Also, because each backup contains a catalog of the data, it's very easy to locate and restore files from the VTL.
Spectra Logic licenses FalconStor's deduplication engine and includes FalconStor's UI in its appliances for management purposes. All other aspects of the appliances are managed through Spectra Logic's own BlueScale management platform. BlueScale provides a common user interface across nTier and other Spectra Logic storage systems. From the BlueScale UI, I was able to see how effective the deduplication engine was, manage and maintain my virtual tape libraries, and define my replication schedule. I found it to be pretty intuitive to use after a few initial minutes of exploration.
The Spectra Logic nTier family of VTL appliances does an excellent job of standing in for physical tape drives and libraries, allowing for either a migration away from physical tape, or as an intermediary to physical tape to make it more efficient. Through iSCSI, each virtual drive looked like a physical drive to my backup software, and the deduplication engine worked well in all scenarios. The management UI was easy to navigate, although defining the virtual tape libraries was a little daunting. Nevertheless, for enterprises that want to keep the look and feel of tape but migrate to disk-based deduplication, the nTier family is a perfect fit.
With the exception of the VTL components, Spectra Logic's management console looks and functions exactly like FalconStor's, providing an excellent quick view of disk usage and deduplication statistics.