Infortrend Inc. began shipping a new disk array this week made up of 2.5-inch SAS disks, the first networked version of a subsystem using the smaller SAS form factor to hit the market. Analysts say the small form factor could show up in enterprise SAN arrays by early next year, with adoption driven by power and space constraints, and archiving needs.
The Infortrend EonStor B12S-R/G1030 SAS-to-SAS and B12F-R/G1430 Fibre Channel-to-SAS arrays join Hewlett-Packard Co.'s (HP) MSA50 and 70 arrays as the only small form factor SAS subsystems shipping. While the MSA50 and 70 are positioned as direct-attached arrays, Infortrend's B12F Fibre Channel array can be networked and used as a SAN.
The B12S and B12F are available in single- and dual-controller models, but each scales to just 1.8 TB raw. Because they're meant for severely space-restricted data centers, a 1U form factor for the enclosure was more important than packing in more capacity, according to Infortrend vice president of sales and marketing Alan Johnson. He said there's no technical restriction keeping Infortrend from releasing higher capacity models.
"This is just the way technology adoption cycles work," said Greg Schulz, founder and analyst with the StorageIO Group. "You'll see it first in lower price bands, and from there it will move up into higher end storage arrays."
That's been the case with 3.5-inch SAS disks. They showed up first in servers where their comparable performance and relative low cost made them popular. Most enterprise storage vendors have added support for SAS to networked storage arrays over the last year, though most of those offerings do not go beyond 10 TB for a single device.
Because they require the redesign of array enclosures to accommodate their smaller size, 2.5-inch SAS is expected to have a slower adoption curve. However, IDC research vice president for enterprise storage systems Benjamin Woo said the adoption rate could be accelerated by the attention paid to power and cooling in the storage industry, as well as companies' needs to retain massive amounts of data. "You'll start seeing products from larger Tier 1 and Tier 2 OEM manufacturers introducing the 2.5-inch form factor as early as the end of this year," Woo said.
Schulz said storage vendors might skip 3.5-inch SAS altogether and focus on developing small form factor arrays instead. "Over the next 18 months you're going to start to see SAS proliferate more and more in enterprise arrays, with 3.5-inch SAS and 2.5-inch SAS developing in parallel," he said.