Apple has released an update to Xsan, the company's shared SAN (storage area network) file system that enables enterprises to group together storage attached to individual servers as part of a single collective storage pool. Xsan 2 offers easier setup and deployment, enables users on a single workstation to access multiple Xsan volumes at the same time, supports Spotlight searching, and is now qualified to work with third-party RAID storage. (Xsan's previous version did support third-party RAID storage, but Apple didn't emphasize that fact). The software is available immediately.
Xsan is actually an Apple-branded version of Quantum's StorNext File System software, ported to work on Mac OS X, and sold at a significantly lower price. Xsan costs $999 for each Mac attached to the shared file system; Quantum's versions are priced from $1,750 to $3,000 for Windows, Linux, and Unix versions. As far as I can tell, as with Mac OS X Server, Apple offers no upgrade discounts.
The fact that Xsan 2 works with third-party RAID storage is particularly important because Apple has thrown in the towel on the Xserve RAID, quietly removing it from their Web site and directing potential customers to the Promise VTrak E-Class RAID Subsystem. The Xserve RAID was increasingly long in the tooth, relying as it did on Ultra ATA drives instead of modern SATA and SAS drives, and suffering from controllers that weren't active/active failover controllers (meaning that if one controller failed, you lost access to that side of the RAID, and replacing it required bringing the entire RAID down). In comparison, the Promise VTrak E-Class RAID features fully hot-swappable SATA or SAS drives, dual hot-swappable RAID controllers (each one of which can run the entire RAID), support for more RAID levels than the Xserve RAID, and a 4Gb Fibre Channel interface instead of the Xserve RAID's 2Gb interface.
On the MacEnterprise list, comments about the specs on the Promise RAID were almost entirely positive, although one poster had less-than-stellar experiences with other RAID models from Promise.
The fading away of the Xserve RAID may indicate that the product had outlived its utility. According to Andrew Laurence of the University of California at Irvine, "Xserve RAID created a new category when it came out: robust storage using extremely cheap (ATA) disks. As time wore on many other vendors descended into that space, using ATA and then SATA disks."
IT analyst John Welch concurred, noting that there aren't significant margins to be made in the low end of the cutthroat RAID business, and although Apple could have re-engineered the Xserve RAID, "they couldn't bring enough to the table to make it worth the effort." He went on, "The idea of an Xsan/Final Cut Studio hardware certification program also gets much easier to swallow, since RAID hardware manufacturers are no longer competitors, but partners. I can't find much of anything bad about this decision."
While agreeing that the Xserve RAID desperately needed an update, Chuck Goolsbee of Web hosting company digital.forest defended the product, noting that they had never seen any component of an Xserve RAID other than a disk fail, despite having more than 100 terabytes of Xserve RAID storage online. He said, "It is a shame that the Xserve RAID is another Apple product cul-de-sac. They literally changed the game but never exploited the advantage."
None of this indicates, though, that Apple is backing down from the enterprise market entirely, especially given the recent update to the Xserve itself (see "New Xserve Goes Eight-Core Too," 2008-01-08). Instead, Apple is focusing its efforts on areas that can leverage advances from other divisions within the company, such as Macintosh hardware design.
As Andrew Laurence said, "For Apple, I imagine the Xserve RAID calculation came to 'We no longer need to be here.'"