Seagate to Use 2.5-inch Drives in Servers

Seagate claims the move will enable OEMs to consolidate their data centers.

Seagate Technology has announced its intention to shift disk drives designed for servers to a 2.5-inch form factor, claiming that OEMs will be able to consolidate their data centers.

The drive maker did not give a firm timetable for the shift, and executives said that the transition will likely take place over a period of years.

Although Seagate won endorsements from some industry players, it will have to convince a swath of customers across several segments to design what will in effect be custom products. Seagate executives also acknowledged that a second drive makers support will most likely be needed to win customers over.

In general, 3.5-inch disk drives have been used inside the desktop PC and server cages because of their mix of high performance and low cost. Drives with platters measuring 2.5 inches in diameter have been reserved for mobile PCs, primarily because their smaller mass is both lighter and generates less heat. While ruggedized 2.5-inch drives designed for laptops have been used inside blade servers, Seagates products are not being designed to be jostled around inside notebook PCs.

But Seagate executives argued that some of the characteristics that have made 2.5-inch drives attractive to laptop makers also apply to servers. Microprocessor makers such as Intel Corp. have worked with customers like Hewlett-Packard Co. to design blade servers and multiprocessor servers that pack several CPUs in as tight a space as possible. Seagates argument is that this approach can be applied to storage as well.

"How I would summarize this is that key customers have been requesting smaller drives and smaller systems," said Brian Kraus, worldwide product manager for Seagate. "The fundamental issues are that they need to consolidate all of the hardware they have—do I have more or less space? This emergence in trends results in a coming together, a perfect storm. The time is at hand for 2.5-inch drives to put higher-performing hardware into data centers."

According to Kraus, data centers will be able to fit a greater number of 2.5-inch drives inside a rack than 3.5-inch drives, in part due to the drives smaller size and the smaller thermal output.

While the capacity per disk drive will be smaller than a 3.5-inch model, the overall capacity will be the same, Kraus said. Meanwhile, the increased number of heads and disks means that the drives will be performing about the same number of read/write operations as a server based on 3.5-inch drives, but require a smaller amount of space.

More importantly, 1U servers will be able to hold a full RAID 5 array—four disks to store data, with a pair of redundant disks for the operating system—while a similar setup using 3.5-inch disks would be forced to use a 3U configuration, Kraus said.