Adaptec has added three iSCSI-only storage subsystems to its SnapServer line, and aims to go head to head with NetApp, EqualLogic, LeftHand and even Dell/EMC in the market for mid-sized storage area networks, or SANs.

"This is a new product for a new market segment, namely mid-tier iSCSI targets," said Adaptec marketing director Don Chouinard. "That's sub-$50,000 boxes with maybe 3-60 drives, for example the Dell/EMC AX150i."

The Adaptec iSCSI family is called the SnapServer 700i and offers from one to 36TB of storage for application servers, using combinations of SAS and SATA drives.

It uses the same hardware as current high-end SnapServers, but with the addition of an Adaptec hardware RAID controller, up to four Gigabit Ethernet ports and a new operating system called OnTarget OS. Like Adaptec's current GuardianOS, this is Linux-based, but where GuardianOS supports NAS and iSCSI, OnTarget is iSCSI-only and can only serve up block storage, not files.

Chouinard claimed that the enhancements mean the 700i's iSCSI performance is four times that of the "dual-dialect" SnapServers.

"Previously, our boxes didn't provide the same iSCSI performance as the 700i, but they were on a par with most of the boxes based on Windows Storage Server," he said. "They were mainly used for NAS, and iSCSI was an afterthought. About 10 percent of our customers used it.

He added, "The new systems have been tested with Linux, VMware and Windows iSCSI initators. We worked with Microsoft to put in Simple SAN compliance, cluster support and support for diskless boot from SAN, and we wrote an MPIO driver - there's a lot of server work involved here."

MPIO means that two 700i units can be mirrored and then connected to duplicate clustered Windows servers via duplicate Ethernet switches, say, with MPIO handling fail-over between the storage devices.

The 700i also comes with new storage management software. This can not only set up and mask volumes on the SnapServer itself, it also helps the administrator set up and assign them on the server, said John E Quigley, senior network engineer at Total Quality Logistics, which was an early customer for the new system.

"I was not only impressed with the outstanding speed of the new SnapServer, but also how quickly and easily we were able to set it up," he said. "The initial configuration was very simple, and the interface clean and easy to navigate. As a result, we were able to attach servers literally within minutes, and they work great."

The 700i supports both SAS and SATA drives - indeed, it's the the main differentiator between the three standard models, with the 720i and 730i having four SATA disks, for cheaper bulk storage, and the top-of-the-line 750i having four high-performance SAS drives. (The low end systems also have only 1GB of system RAM, vs 2GB in the 750i.)

The main alternative to iSCSI for networked application server storage is Fibre Channel SAN gear. Fibre Channel pricing has tumbled in recent years, as vendors try to persuade mid-sized organisations to buy into SANs, and its speeds have doubled and re-doubled, with 8Gbit/s now in testing.

However, Chouinard said that while few current Fibre Channel users were likely to rip-and-replace, iSCSI remains the cheaper option for companies that don't yet have a SAN.

He said that starting prices range for the 700i family range from £4100 for a 720i with 1TB of SATA disk, to £11,900 for a 750i with 1.2TB of SAS. All models can accept additional external SAS and SATA, in the shape of 12-drive Adaptec SANbloc modules. Storage from other suppliers can't be included, but existing SANblocs from other SnapServers can be re-used, he added.

The new systems could also reassure Adaptec customers worried about the company being forced out of the storage systems business. Chouinard said they demonstrated Adaptec's intent to grow its systems division.