Xyratex has introduced a new 4835 drive array enclosure. It can hold up to 48 SATA drives with a capacity of 24TB when 500GB drives are introduced later this year by the main drive vendors. You won't find Xyratex-branded drive arrays though; instead Xyratex sells through OEMs, such as Network Appliance.Jon Haley, Xyratex' VP for sales and marketing, says: "NetApp is our largest OEM."

Xyratex has produced the 4835 in response to customer demand. Haley says: "IDC says the maket for high-capacity, low-cost storage will groww - in 2008 to $15 billion. There's a reducing $/GB requirement."

"Our (4835) product provides nearline storage. It's not just tape emulation, it's an online/nearline-capable system."

No need for MAID service
Copan Systems has its MAID concept (Massive Array of Idle Drives) in which hundreds of drives are packed into a rack but only some of them are active. Thus enables Copan to overcome the cooling problems of having such a dense array.

Xyratex has packed 48 drives in an enclosure and up to 7 4835s could be put in a rack, according to Haley. That's 336 drives. It's not as many as Copan's Revolution 200T which packs up to 896 drives in a rack. They are in 8 shelves, with 112 drives per shelf, 8 canisters per shelf, and 14 drives per canister.

Xyratex relies on air cooling as does Copan. But with all the drives active there is a lot of heat to disperse. Haley says: "There's a cooling challenge there; in getting the right amount of cooling air through. It's one of our key strengths. We use a large amount of computer simulation."

Concerning Copan's MAID he says:" We can achieve comparable performance with Copan Systems." He emphasises that the Xyratex drives are online all the time. There are no quiescent LUNs or volumes.

Certainly the 4835 could be used for the tape replacement market. The general application is one where: "People are staging their data."

The Xyratex arrays are, Haley says, easier to maintain: "Everyone of our arrays is effectively removable. You can repair volumes and LUNs online without having to shut the system down. There is a full high-availability design with redundant components."

"The Copan system is very much like a tape library with a set of drives. YOu need to take a LUN offline to repair a SATA drive failure."

How do you like your tape emulation?
Xyratex' 4835 can be used for nearline storage or tape emulation. The Copan system is for tape emulation only - unless you don't mind your nearline storage being offline some of the time.

Xyratex will provide up to 168TB of storage, with the coming 500GB drives. Copan will provide, assuming the same drives are used, up to 448TB. If you want capacity for tape emulation then Copan has the edge. If you want access speed for nearline storage then Xyratex has has the edge. In keeping with the access emphasis its drives can be repaired without taking the array or array section down.

As most of the Copan drives are offline at any one time repair to a drive section can be done with that part of the array offline.

It is, in effect, horses for courses.

Full circle
For lovers of irony, the Xyratex arrays are interesting. The firm is a buy-out of the IBM Havant drive array plant. It supplies drive enclosures to Network Appliance. IBM resells NAS products produced by Network Appliance. So the Xyratex arrays have come full cirle, out of IBM, as it were, and back into IBM again.