Weekly quickTIP

The Incredible Shrinking Disk

Windows 2008's nifty disk-manipulation features includes this cool disk-shrinking tool that has nothing to do with cold water.

Windows Vista comes with a boatload of nifty new features, but one that continues to excite me is its enhanced ability to manipulate disks. With previous versions of Windows, we could expand volumes with the DISKPART command or append new ones to create larger volumes. But at no point with the native tools were we ever able to make those volumes smaller.

If you’re like me, when you build a new computer you sometimes scratch your head when the option arrives asking for volume size. More often than not, I usually create a volume that’s as big as the disk itself. But sometimes I need to create multiple volumes on the same disk. Maybe I have a concern about log files filling up the system drive. Maybe I want to split apart my data drives from my system drive for easier recovery in case of a failure.

In either case, creating a volume at the wrong size usually meant extra work down the road to fix that size when it became apparent I’d made a mistake. With Vista and Windows Server 2008, however, those problems go away.

Right-click the Computer icon on any Vista or Windows Server 2008 computer and open Computer Management (for Vista) or Server Manager (for Windows 2008). Navigate down to Disk Management and right-click again on any available disk. You’ll see three new items in the context menu: Extend volume, shrink volume and delete volume.

By far the neatest of these is the ability to shrink a volume. Obviously the shrinkage of that volume will depend on how much data is on the disk, but what’s unbelievably cool about this new capability is that it can be done without impacting the OS. You can even shrink the system drive while the system is actively running on the drive. There are a few limitations:

Tech Help—Just An
E-Mail Away

Got a Windows, Exchange or virtualization question or need troubleshooting help? Or maybe you want a better explanation than provided in the manuals? Describe your dilemma in an e-mail to the MCPmag.com editors at [email protected]; the best questions get answered in this column and garner the questioner with a nifty Redmond T-shirt.

When you send your questions, please include your full first and last name, location, certifications (if any) with your message. (If you prefer to remain anonymous, specify this in your message, but submit the requested information for verification purposes.)

  • You can only shrink NTFS or unformatted partitions.
  • Disks with too many bad clusters will not be allowed to shrink.
  • Unmovable areas on the disk like the page file or shadow copy storage area can impact how far down the disk can be shrunk. If your disk cannot shrink to the size you want, consider removing these elements first.
  • Only administrators can manipulate disks.

If you prefer the command line, the command-line tool DISKPART has similarly been augmented with these capabilities. The command you’ll want to look for is SHRINK DESIRED={Desired amount of size reduction} MINIMUM={Minimum amount of size reduction}. By including both the DESIRED and MINIMUM switches in the command, DISKPART will attempt to reduce the size by the DESIRED amount. If it can’t, it’ll at least attempt to reduce it by the MINIMUM amount.

About the Author

Greg Shields is Author Evangelist with PluralSight, and is a globally-recognized expert on systems management, virtualization, and cloud technologies. A multiple-year recipient of the Microsoft MVP, VMware vExpert, and Citrix CTP awards, Greg is a contributing editor for Redmond Magazine and Virtualization Review Magazine, and is a frequent speaker at IT conferences worldwide. Reach him on Twitter at @concentratedgreg.

comments powered by Disqus
Most   Popular