History 2002: From Netpp, First Enterprise Backup System Based on Disks

Although EMC is better known for disliking tape, it was NetApp that was first to release a complete enterprise storage subsystem for backup using only disks.

Its new NearStore closely resembles any other NAS filer, but it contains low-cost Maxtor IDE disk drives at 160GB each in the classic RAID-4 level NetApp has always preferred, for a total capacity from 12TB up to 96TB.

NetApp does not present the product as a tape killer but rather as a “centralized rapid recovery and backup consolidation solution,” a “complementary technology for traditional tape backup solutions” that will fit between one or more primary storage NAS via an Ethernet connection, on one side, and a tape library connected by FC interface on the other.

Snapshots of the filer are stored on NearStore initially, then sent to tape using NDMP.

Even so, Dave Hitz, founder and VP engineering of NetApp, can’t help but make the comparison: “The IDE drives are low-cost, slow and not as reliable as high-end drives, but they are faster and more reliable than tape drives, and easier to manage.”

The most immediate advantage of these new near-line storage units is the considerably more rapid recovery of backup data, which now moves from a primary storage disk to a secondary storage disk, and back, if necessary.

NearStore’s release date is still fairly vague, sometime in 1FH02. Its price is announced at roughly 2 cents per megabyte. More specifically, a 12TB model will cost $245,000. In fact, the total acquisition value of the drives, including parity units, barely exceeds $30,000, since a 160GB Maxtor unit costs about $300 (or .2 cents/MB). Even adding in the controllers, etc., that leaves a healthy margin for NetApp.

What’s most interesting about all this is the novel idea of backup on other devices, something that will no doubt inspire imitators. Some aspects, of course, could stand improvement. It would, for example, be preferable to connect NearStore directly to filers via SCSI interface, or better yet FC/SAN, rather than on the same Ethernet network to which all enterprise servers are already connected.

It is conceivable that NearStore could provide secondary storage to non-NetApp NAS solutions, and even to SANs. Such thoughts are in the air. Will it eventually backup EMC’s Symmetrix?

“Not yet,” responds Hitz, who doesn’t say no, with the use of third-party software from Veritas or Legato, in which case backup on disk would be effected in tape data format.

Although we salute NetApp’s innovation with NearStore, product deserves improvement, and more importantly, remains expensive compared to classic backup on FC tape libraries.

Disk arrays are entirely competitive for backup of small capacities, but for larger needs, the much lower price of tape media generates obvious economies. So the question is: are users prepared to pay that much more to enjoy the convenience of near-instant restore functionality?

This article is an abstract of news published on issue 168 on January 2002 from the former paper version of Computer Data Storage Newsletter.