Do mobile disk drives have a future in disk-based backup? Tape library maker Spectra Logic thinks so.
Spectra's T950 tape library can now be equipped with a RAID Exchangeable TeraPack (RXT) drive, a disk-backup option built around 12 2.5-inch 80GB mobile-class disk drives, configured as either RAID 0, 1 or 5 (see "When old is new again"). And because it's the same size as Spectra's TeraPack media casing, it can be removed for off-site storage.
Another RXT model comes with two 400GB 3.5-inch desktop-class drives, configured as RAID 0 or 1. It's cheaper than the mobile drive version--$2,000 vs. $6,000--but with no RAID 5, it provides limited capacity or data protection. "The more compelling proposition is a RAID 5'd TeraPack," says John Woelbern, a Spectra Logic consultant.
Compared to desktop drives, mobile drives have other reliability benefits, Woelbern says. For example, they require less power and generate less heat. Plus, they don't suffer from disk "stiction"--where the head adheres to the media--because the heads are parked to the side when not in use.