Microsoft Adds Much-Needed Storage Features to New OS

Several new storage management features have been added to Windows Server 2003, and related APIs have been released to third-party storage vendors to allow them to make use of these features, said Zane Adam, director of product management and marketing for Microsoft's Enterprise Storage Division.

Solution providers have said the storage management technology included in previous Windows operating systems (OSes) needed improvement.

Among key enhancements in the new OS is Virtual Disk Service (VDS), which enables the management of multivendor storage devices, Adam said. VDS gives Windows its first native Logical Unit Number (LUN) masking capability, which allows certain portions of a storage device to be reserved for use by specified hosts.

"LUNs have become transparent to other applications," he said. "Partners like EMC and Hewlett-Packard can use our APIs. ISVs can also do LUN masking through our APIs while adding their own value."

Another big step for Microsoft is Volume ShadowCopy Service (VSS), which allows point-in-time copy capabilities to be integrated between the operating system and applications, Adam said.

"Today, you can take a copy of the data, but the application does not know the copy is being made," he said. "If a copy is taken while the data is being used by the application, the copy can be corrupted. Now the application can be [temporarily disabled] during the backup. Third parties can develop applications using the VSS API."

Other new features in Windows Server 2003 enhance Windows' SAN management capabilities, include volume monitoring, Adams said. "In the old days, the [Windows] operating system would assume that any disk in a SAN belongs to it," he said. "Now users can designate which part of a SAN goes to which host."

Also included is Multi-path I/O (MPIO), which Microsoft introduced about six months ago. MPIO allows 32 paths to data, and if a path fails, the data movement is load-balanced between the other paths, Adam said.

In June, Microsoft also plans to release native iSCSI drivers and introduce a logo program to certify iSCSI compatibility with its operating system, Adam said.

Migrating legacy applications to the new Windows Server 2003 before they are rewritten for the new operating system should not break those applications, Adam said. "But they won't be able to take advantage of the new APIs," he said.

Major storage hardware and software developers are preparing to roll out new versions of their storage management applications that take advantage of the new Windows storage features.

However, at least one solution provider warned that it is still way too early to deploy Windows Server 2003 in an enterprise setting.

"If anyone tries to implement those new features in a Windows environment is the first six months, they're braver fools than me," said Doug Marlin, managing partner of at Independent Technology Group of La Canada, Calif. "Microsoft doesn't have the greatest track record with new releases."

The new storage-management features are welcome additions to Windows, Marline said. However, he called the features "yesterday's news" because they have been implemented in other operating systems for some time.

Also, Marlin said, he is not sure that putting such features in the operating system is the right way to do it. "They should be done at the (SAN) fabric level," he said. "But is Microsoft, so it will have an impact."

For instance, adding LUN masking and MPIO to Windows is a good move, Marlin said. But that begs the question of how such features interface in a multiplatform environment, given that enterprises almost never use a single operating system, he said.