Their Reliability On The Rise, ATA Hard Drives Move Up The Storage Ladder

The arrays, which use the same ATA hard drives used in most desktop PCs, are also finding their way into disk-to-disk backup solutions as customers look to speed their backup and recovery processes and eliminate the need to duplicate expensive storage arrays across multiple sites.

ATA hard drives have been used in storage arrays for about five years and, as their reliability increases, are becoming more useful for business applications, said Jim Porter, president of Disk/Trend, a Mountain View, Calif., consultancy.

In the past, the mean time between failures (MTBF) of ATA drives has been about 100,000 to 200,000 hours, or about 20 to 30 years, compared with about 1 million hours, or 114 years, for SCSI or Fibre Channel server hard drives, Porter said. However, vendors have started offering ATA hard drives,both with the current parallel interface and the upcoming serial interface,with an MTBF of 1 million hours as well, he said. Using them as part of a RAID system also prevents data loss if a drive fails, he said.

Such arrays are also starting to be deployed at remote sites for disk-to-disk data backup, said Porter. "In the past, remote site mirroring arrays cost the same as the primary storage arrays," he said. "With ATA arrays, this can now be done at one-fifth to one-half the cost."

Porter cautioned that ATA hard drive arrays are not designed for data archiving. "There, you need removable storage media so that if the IRS comes to you 10 years [after you file a tax return, you can rebuild the data," he said. "But for simple protection against catastrophes, you can go with ATA arrays at remote sites."

John Zammet, president of HorizonTek, a Huntington, N.Y.-based solution provider specializing in data backup and archiving, said some of his customers are satisfied using ATA-based arrays for both primary storage and disk-to-disk backups.

But Zammet cautioned that such arrays essentially use hard drives designed for PCs.

"[ATA drives were designed for use eight hours a day," Zammet said. "But people are using arrays for high-availability systems banging away for 24 hours a day. Vendors recently cut their ATA hard-drive warranties to one year because of problems with high-availability RAID systems."

Nexsan Technologies, Woodland Hills, Calif., recently introduced its ATAbeast, a 4U enclosure with up to 42 hard drives. Using the 320-Gbyte hard drives that Maxtor is expected to release by year's end, the array's total capacity is up to 13.5 Tbytes, said Diamond Lauffin, senior executive vice president at Nexsan.

ATAbeast includes dual controllers and is the only high-density array that uses hot-pluggable hard drives as opposed to the typical sled-mounted drives, Lauffin said.

ATAbeast is expected to ship this month using 250-Gbyte hard drives, with commercial quantities available in early February, he said.

The company also just introduced ATAbaby, a 1U enclosure with up to 750 Gbytes of capacity after RAID formatting. That product is priced at $2,995.

Nexsan sells only via solution providers, Lauffin said. ATAbaby gives solution providers a margin of about 35 points, compared with 40 points for ATAbeast, he said.

San Diego-based nStor Technologies is planning to ship a variation of its 4000F array, which fits up to 12 Fibre Channel hard drives into a 2U chassis, said Aaron Dunford, director of marketing at the company. The new model, expected to start shipping this month, will use serial-ATA hard drives and will offer a choice of Fibre Channel or iSCSI connectivity, depending on the interface card, Dunford said. NStor is recruiting solution providers to sell its products.