Windows Server 2003 means better storage management

By Lisa Coleman

This month, Microsoft finally introduced its long-awaited Windows Server 2003, which includes new storage management capabilities as well as other features.

However, analysts say that the new storage management features are just the tip of the iceberg, and that Microsoft will get even more aggressive with data management in the next 12 to 18 months.

"Microsoft is quickly setting up the foundation to influence where data resides, how it's managed, and to a great extent, how it's leveraged," says Jamie Gruener, a senior analyst with The Yankee Group consulting firm.

Microsoft has been architecting its storage initiatives for a few years. In 2001, it optimized its operating system for OEMs to build "Windows-Powered" network-attached storage (NAS) servers, which rapidly gained market share in the NAS market. Last year, the company formed an Enterprise Storage Division. Meanwhile, work began to develop new storage management features to improve operating system performance in storage area networks (SANs).

One of the most important new storage features in Windows Server 2003 (see table on p. 16), and the one that analysts tout as a necessity for midrange and high-end functionality, is snapshot capability.

Microsoft's Volume Shadow Copy Service (VSS) provides an infrastructure for creating point-in-time copies of a single volume or multiple volumes.

Essentially, the snapshot capability is now built into the operating system, as opposed to being implemented in appliances. VSS coordinates with business applications, backup applications, and storage hardware to enable application-aware data management. The application coordination is a key differentiator. For example, a third-party backup product that takes advantage of the VSS API can now take a snapshot by coordinating and communicating with the operating system. The operating system, in turn, coordinates with SQL, or another server, to flush its cache, take a new transaction, make a snapshot, and hand the snapshot to the backup product.

"Now the OS, the backup application, and the application itself are all coordinated, and that makes the integrity of the snapshot higher," says Zane Adam, group product manager in Microsoft's Enterprise Storage Division.

In addition, the Enterprise Edition of Windows Server 2003 will offer "transportable snapshot" capability, enabling a SAN to use the VSS API for snapshots, says Adam.

Another new feature that will enable Windows Server 2003 to interoperate with SANs is Virtual Disk Service (VDS). VDS implements a single, uniform interface for managing disks based on a set of APIs. Hardware vendors write a VDS "provider" that translates the general-purpose VDS APIs into specific instructions for their hardware. Management applications will no longer need to take into account the specific hardware being targeted. Instead, by developing applications that target VDS, Windows Server 2003 disk management applications will be able to manage any hardware that has a VDS provider.

Currently, there are about 30 vendors using the VDS API.

VDS could also be a gateway for bigger initiatives, speculates Yankee Group's Gruener. He adds that ultimately, through VDS, data can be classed and categorized to make it application-centric.

"Microsoft isn't saying that they will do that. What they are saying is that they will enable more intelligent ways to do that. I see them playing a fundamental role in accelerating a lot of different kinds of content-focused storage," says Gruener.

In the past, Microsoft has not been very "SAN-friendly," say analysts. It did not support Fibre Channel in its previous operating system, and host bus adapter (HBA) installation was time-consuming, especially if hundreds of servers were tied to a large SAN. But as more and more SAN deployments are Windows-based, there is a real need for Windows to support SANs.

"SANs are much more of a reality today than when Windows 2000 was designed," says Microsoft's Adam. "Windows servers front-end a lot of SANs, so we have to make sure we have feature sets that make it reliable for SAN environments."

While both VSS and VDS offer capabilities to make Windows Server 2003 more SAN-friendly, Microsoft also added Fibre Channel SAN handling, support for the SNIA HBA APIs, and support for iSCSI. (For more information about iSCSI and Microsoft's play in that space, see the Special Report, p. 18.) But perhaps most importantly, Microsoft has made it much easier for administrators to control volume mounting.

Previously, when a Windows server was installed in a SAN, the server would put its signature on all disks and volumes. This occurred because the software was designed more for local disks than for SANs, explains Microsoft's Adam. With Windows Server 2003, administrators can control how much disk and which volumes in a SAN are available to each server.

In addition, Microsoft enhanced its boot-from-SAN function. While this capability was available in Windows 2000, it is simpler to use in the 2003 edition, according to Adam.

Boot-from-SAN enables easier management, separation of processor, and disk virtualization, and will eventually enable diskless servers to boot from a SAN.

Microsoft is also providing a driver development kit to its partners for multipath I/O (MPIO) technology, which provides a standard and interoperable I/O protocol for communicating between third-party storage products and Windows. MPIO is not a feature of the operating system but is available separately to storage vendors.

MPIO technology enables more than one physical path to access a storage device. Having multiple paths available between servers and storage improves load balancing, availability, and fault tolerance.

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Microsoft also made a handful of other tweaks in Windows Server 2003 for improved backups, security, and availability.

The Enterprise and Datacenter versions of Windows Server 2003 will offer an enhanced distributed file system (DFS)—which virtualizes namespace—allowing multiple DFS roots on a single server.

Windows 2003 features bare-metal recovery and installation of the operating system via Automated System Recovery (ASR). In addition, Microsoft's backup utility can now perform open file backups.

Microsoft has also improved its encrypting file system so that additional users can be authorized to access encrypted files. Encryption will be available for offline files.

Windows-Powered NAS

In about 90 days, Microsoft will release Windows-Powered NAS version 3.0. The next-generation NAS server appliance kit (SAK) will be based on Windows Server 2003 and will offer the same storage features, according to Microsoft's Adam.

Windows-based NAS quickly gained traction after its debut in 2001, and by the end of 2002 it had captured almost 30% of the NAS market, according to International Data Corp. Analysts predict it will continue to gain ground as the NAS market grows from $1.65 billion in 2002 to $4.1 billion in 2006.

This article was originally published on April 01, 2003