Microsoft Hobbles Next Windows Home Server

Microsoft this week revealed that it was removing one of the core technologies from the next version of Windows Home Server (WHS), a move that will also impact two related products, Windows Small Business Server 2011 Essentials (previously code-named Aurora) and Windows Storage Server 2011 Essentials (previously code-named Breckenridge). The feature, called Drive Extender, was responsible for data duplication and storage pooling.

Microsoft's public stance is that Drive Extender was killed because of "feedback from partners and customers about how they use storage today and how they plan to use it moving forward," noting that today's larger hard drives reduces the need for Drive Extender. While the company is clearly seeking to put a less negative spin on a major step back, that statement doesn't really explain why Drive Extender was cancelled.

While Drive Extender was previously used only in a niche product, WHS, Microsoft's intention was to move it forward to more mainstream Windows Server and then Windows client versions. The benefits were to be enormous: Drive Extender could be used to silently and seamlessly ensure that each file in storage is replicated across two physical hard disks, helping to prevent data loss in the event of a hardware failure, and doing so without the complexities of RAID. And Drive Extender's storage pooling largely eliminated the need for drive letters, simplifying storage allocation dramatically.

So Microsoft moved Drive Extender into SBS 2011 Essentials and Storage Server 2011 Essentials. These products will be used much more like typical servers than WHS, however, and Microsoft and its partners quickly ran into data integrity and reliability issues with certain classes of server applications. The company attempted to fix Drive Extender to meet the needs of these important server applications but ultimately decided it was unable to do so.

Because mainstream Windows Server products are more important to the company and its partners, Microsoft decided to axe Drive Extender. In a briefing last month, the software giant explained to me that the decision was final, and that Drive Extender would not be reappearing in the future.

"Drive Extender was a neat feature, but the implementation was off, and we discovered some application compatibility and disk tool problems related to its ability to correct data errors on the fly," Microsoft General Manager Kevin Kean told me at the time. "We don't want to give customers problems; we want to give them solutions. So ultimately, we decided that we needed to cut out Drive Extender. Removing Drive Extender will make file shares easy, and it's possible to accomplish most of its features otherwise. For example, you use the server's centralized backup or even RAID as an alternative to data duplication."

It's likely that more traditional storage technologies can make up for the missing Drive Extender features in SBS and Storage Server, as those products are already well-served by a thriving partner ecosystem. The problem, of course, is WHS: A much smaller user base combined with fewer engaged partners suggests that this product may be on the ropes. Microsoft will deliver a new Drive Extender-less beta of the next WHS product, codenamed Vail, and of SBS 2011 Essentials, in January. And at that time, we'll be able to evaluate whether WHS, in particular, makes any sense with its heart ripped out. Because of the Drive Extender fiasco, both products were delayed until some vague time in the first half of 2011. Both were originally expected by the end of this year.

This is personally disappointing because I've been one of WHS' most public proponents, and I felt that the mix of features offered by the product, underused as it is, made it the ideal infrastructure for home users, home businesses, and even very small businesses. (It's what I use, in fact.) Microsoft apparently agreed, as it used WHS as the basis for both SBS 2011 Essentials and Storage Server 2011 Essentials. But with Drive Extender removed, it's unclear whether WHS Vail will be as compelling as its predecessor, given the rise of alternatives like Drobo and more functional NAS (network-attached storage) devices.

I guess we'll find out in January.