Microsoft’s new OS catches up on storage

InfoWorld (US)

Judging by advances in Windows Server 2003, Microsoft Corp. is dedicating more resources toward bolstering storage capabilities. The impressive list of new or improved features covers a wide spectrum, including better performance (Microsoft suggests that the NT File System is faster than in previous releases), better file and volume management, and much-needed extended support for networked storage.

Microsoft has made strides to improve the storage friendliness of Windows Server 2003. Beyond built-in support for the emerging iSCSI storage networking protocol, which should be available free in June, the company is opening in the OS a set of APIs named VDS (Virtual Disk Services).

Developed to be used in partnership with other vendors, VDS establishes a lingua franca inside Windows Server 2003, allowing administrators to use scripts or the MMC (Microsoft Management Console) to easily and dynamically change volume allocations, regardless of the storage device’s brand.

This approach is a welcome relief for activities such as grabbing new disk volumes. You no longer have the headache of jumping between vendor-specific management tools to perform daily tasks.

The shadow copy knows

Enhancements to VSS (Volume Shadow-copy Service) are also eye-catching. The VSS application called Shadow Copy Restore allows painless recovery of user files that have been erroneously deleted or updated. The minimum context for Shadow Copy Restore is a Windows Server 2003 file server that shares users’ folders across the network.

Depending on your requirements, you can activate shadow copy on a domain controller with Active Directory and DFS (Distributed File Sharing), and on cluster configurations.

The deployment steps for Shadow Copy Restore are intuitive: Set or identify the shared folders to protect, allocate an area in which to store shadow copies of those folders, and create a schedule to automatically take a volume snapshot, at predefined intervals, of files and folders that have changed.

Setting the schedule for shadow copies requires planning. Using a wizard, you can define points in time for the application to create a shadow copy of a volume, based on a start time and an interval or an event, such as user logon.

For example, a typical shadow copy schedule for users’ files could be Monday through Friday, every hour, from 8 a.m. to 6 p.m. With this setting, Windows Server 2003 automatically creates an hourly fall-back image of files and directories modified during that interval so that users can restore the saved copy if the current version is corrupted. Instead of using the GUI wizard, administrators can use the vssadmin command to manage shadow copies from the command prompt or from scripts.

Retrieving previous file versions is a simple matter of bringing up the File Property context menu in Windows Explorer and selecting the new Previous Versions tab. From there, an administrator can see saved files and directories and easily restore them to the original location or elsewhere.

Windows Server 2003 also includes an update to Windows Explorer for client PCs, which allows users to access that same Previous Versions tab. This update makes users self-sufficient in recovering lost or damaged files.

Unfortunately, the Previous Version update can be installed only on Windows XP clients. However, shadow copy is server-based and will protect users’ files regardless of the client. But to restore previous versions, users with older Windows clients will need administrator assistance.

Shadow Copy Restore is not perfect. There is a limit of 64 snapshots per volume, which may be too few for highly referenced folders. Further, administrators cannot specify different schedules for folders on the same volume. Moreover, the changes made between predefined points in time are not saved, which doesn’t give users a full recovery blanket.

Nevertheless, considering that erroneously deleting or modifying a file is one of the most frequent and costly user snafus, the Shadow Copy Restore feature alone, although not perfectly fool proof, warrants an update of your file servers to Windows Server 2003.

Shadow Copy Restore is just one of the possible applications that can take advantage of VSS. For example, consider applying shadow copy to a database and using a point-in-time snapshot as a source for nonintrusive backup operations or analytic applications.

Good market outlook

Similarly to VDS, the success of VSS demands that third-party vendors adopt Microsoft-provided APIs in their solutions. I don’t see why they shouldn’t. Making storage and data more manageable is a common goal for storage vendors, Microsoft, and their customers, who will gladly trade some administration dollars for new solutions that take advantage of Windows Server 2003’s storage-friendly features.

Moreover, the storage related improvements in the OS pay lip service to the next version of WPN (Windows Powered NAS) which should inherit the same improvements in facilitating storage, and should attract even more storage vendors to Windows-based NAS solutions. The recent announcement of HP StorageWorks NAS b3000, a consolidated NAS-SAN environment for Microsoft Exchange 2000 that adopts WPN, indicates that major storage vendors are taking Microsoft’s new approach to storage seriously. You should, too.