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Should you choose a SATA-based array?

The new, "cheap" SATA drives may not be as cost-effective as you think.

This article first appeared in "Storage" magazine in the June issue. For more articles of this type, please visit www.storagemagazine.com.

What you will learn from this tip: How cheap SATA drives really are, and when to choose them. Also: the latest SATA arrays, with specs and prices.

Just because Serial ATA drives cost less than a quarter the cost of Fibre Channel drives on a dollar-per-Gigabyte basis, don't expect those kinds of savings in the new SATA-based arrays from EMC Corp, Hewlett-Packard Co., Hitachi Data Systems and Sun Microsystems. There, the savings shrink to approximately 50%.

According to Chris Wood, director of technical sales and marketing with Sun's networked storage division, the price range for these arrays -- $3/GB to $12/GB -- is consistent across all the major vendors. That makes sense, Wood says, since "we all buy our drives from the same manufacturers."

The latest SATA arrays include:

  • EMC's Clariion AX100, which as resold by Dell, costs between $10.41/GB for a single controller model with 480GB, to $3.12/GB for a dual controller model with twelve 250GB drives. IBM's TotalStorage FAStT100 has a list price of $9.06/GB for a 3.5TB unit. The FAStT100 can support up to four 3.5TB EXP100 disk shelves.
  • Sun's StorEdge 3511, a 12-drive model that can take an additional eight 3TB expansion trays. The unit also comes standard with eight host ports.
  • HP's MSA1500 controller, plus the MSA20 SATA JBOD. A dual-controller pair, plus 2TB of SATA storage, costs about $7.50/GB.
  • HDS' SATA Intermix Option for its Thunder 9500V family. Depending on the configuration, HDS expects SATA drives to cost approximately 40% that of Fibre Channel drives.
Assuming cost is about equal, storage buyers need to consider other buying criteria such as software support or expandability, says Sun's Wood.

Of course, SATA's Achilles' heel is its reliability, which may pave the way for Seagate's new NL35 drive, also a desktop class drive, but with a dual-ported Fibre Channel interface. Dubbed Fibre-Attached Technology Adapted (FATA), Xiotech and HP will offer FATA drives on their respective Magnitude and EVA arrays shortly.

Why not SATA? Midrange customers "don't want to compromise on reliability," says Kyle Fitze, director of marketing for HP's online storage division. They are, however, "willing to compromise on performance."

For more information:

Tip: The advantages of SATA II over SATA I

Tip: All RAID is not created equal

Tip: Guide to low-cost storage

About the author: Alex Barrett is Storage magazine's trends editor.

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