Quantum DLT-V4 review

The development processes for the ValuSmart products has been pedestrian at best. Introduced in 1999 as the DLT1, the second-generation VS-160 didn't appear until early 2003. However, with Quantum at the helm, the third-generation DLT-V4 has made an appearance earlier than expected, which will no doubt please existing ValuSmart users waiting for their next upgrade.

Native capacity is doubled to a healthy 160GB and the new drive uses the same DLT-VS1 cartridges as the VS-160. Alas, performance boosts are in short supply, since this format pushes native transfer rates to only 10MB/sec. This is disappointing, being only a modest 25 per cent improvement over the VS-160. The DLT-V4 achieves these improvements by increasing the number of tracks from 240 to 352 and the recording density from 175KB/in to 219KB/in.

The drive is available as external and internal models, and for the latter Quantum also offers SATA/150 and Ultra/160 SCSI versions, making the family more versatile. The external SCSI drive on review is well built and the half-height form factor of the drive makes for a compact unit.

Two features that make the DLT-V4 stand out are Quantum's DLTSage xTalk utility and its DLTice technology. The first is a diagnostics toolbox that can run a barrage of tests on the drive, while the second is Quantum's response to the demands for standards-based data-archiving facilities. Introduced with the SDLT600, DLTice writes a unique tamper-proof electronic key to tapes selected for WORM duties. This is carried out from the xTalk utility and ensures the tape is now non-erasable and non-rewriteable - data can be appended, but the tape contents can't be altered. A big advantage of the Quantum method is that standard DLT-VS1 cartridges can be used as WORM media.

For performance testing, we used a dual Xeon system running Windows Server 2003 and connected the DLT-V4 to a dedicated Adaptec Ultra320 adaptor card. We used a 9GB mixture of data typically found on a workgroup or SMB server and called in Computer Associates' ARCserve 11.5, Symantec Backup Exec 10d and EMC Dantz Retrospect 7. For each product, the drive was asked to secure the test data, verify it and restore it back to its original location. Both ARCserve and Backup Exec worked happily with the drive without requiring a patch, but Retrospect wouldn't recognise it until we'd downloaded and applied the latest update.

Overall, we were impressed with the DLT-V4, as it exceeded its quoted native transfer rate in every test. For backup, verification and restoration, ARCserve returned 11.8MB/sec, 12.3MB/sec and 10.9MB/sec respectively, while Backup Exec reported 11.9MB/sec, 12.1MB/sec and 11.1MB/sec for the same tasks. Retrospect lagged behind only slightly, delivering 11.1MB/sec for backup, 12MB/sec for verification and 10.7MB/sec for restoration.

Companies that have already invested in DAT drives and are using DDS-4 probably won't be convinced by the DLT-V4. However, those that either don't have a tape-based backup system in place or feel that DDS-4 and DAT72 are no longer fast enough or have sufficient capacity should certainly consider it as an alternative. They could even choose VS-80 or VS-160, safe in the knowledge that the third generation is there and ready for upgrading to in the future.

Author: Dave Mitchell