Quantum LTO-4 HH

No other tape format has had as big an impact on the SMB and mid-range backup markets as Ultrium LTO. Its unbeatable combination of speed, capacity and features has kept HP's StorageWorks Ultrium 1840 on the PC Pro A List ever since we tested it, and now we bring you an exclusive review of Quantum's half-height (HH) version.

We look at the complete kit, which includes a SAS desktop drive along with SAS cable and LSI PCI-E Series 3000 HBA. A differentiator of Quantum's offerings is the xTalk Management Console, which offers a toolbox of utilities for running full diagnostics or selected tests on the tape drive. You also get the handy StorageCare Sage that shows details such as the data written, used and available capacity, and when the next cleaning cycle is due.

The LTO-4 HH on review is presented as a compact desktop unit, but the drive itself will fit in a standard 5.25in bay making it ideal for local server backup. However, the demands of the autoloader market also dictate this reduced height requirement, just as much as it allows vendors to offer greater capacities in smaller rack chassis backup appliances.

There's no payback for the reduced height either, as Quantum quotes the same native 120MB/sec performance and 800GB capacity as the full height LTO-4. Quantum also makes a big play on the green card, since it claims the drive uses up to 46% less power when idle than the competition. It also claims the drive uses less power than an LTO-3 drive during read and write operations.

We ran power comparisons using the LTO-4 HH, an HP Ultrium 1840 and an HP Ultrium 960, but couldn't see any real difference. Using an in-line power meter, we saw the LTO-4 HH draw 15W in idle, the 1840 draw 17W while the 960 took 20W. During backup jobs all the drives registered a maximum power draw of between 35-37W, so there's really nothing in it as far as we're concerned.

You'll need some high-quality hardware to get the best out of an LTO-4 drive, so we installed the complete kit in a Boston Supermicro dual 3GHz Xeon 5160 server running Windows Server 2008. We linked the host server into the labs 4Gbps FC SAN and used the latest Infortrend EonStor 4Gbps FC SFF SAS disk array as a backup source for our 17.5GB test data sample. Backup software came courtesy of the bundled Symantec Backup Exec v12, and we also tested with CA ARCserve r12.

For backup operations Backup Exec and ARCserve reported respective averages of 87MB/sec and 86MB/sec, while a full restore back to the disk array returned 104MB/sec and 106MB/sec. Verification speeds differed significantly as Backup Exec delivered 109MB/sec, but it's worth noting that it merely assumes the data is present and correct if it can read each file header. ARCserve provides full tape-to-disk verification and this returned 71MB/sec.

Quantum's LTO-4 HH may not have achieved the quoted native transfer rate during our real-world testing, but it certainly isn't a slouch either. Mix its comparatively high transfer rates with LTO-4's standard AES-256 data encryption support and WORM capabilities, stir in the tasty price tag for the complete desktop kit, and you have a recipe for backup success.

Author: Dave Mitchell