One of the most frequent questions I see on forums and newsgroups that deal with virtualization is the age-old question of “I have used all the space inside a VHD hard disk. How do I expand the virtual hard disk to make room for additional data?”. Luckily for us, with Microsoft Hyper-V on Windows Server 2008, this is now possible. Hyper-V now adds the ability to increase the maximum size of a virtual hard disk. Expanding the disk increases the storage capacity of a dynamically expanding virtual hard disk or a fixed virtual hard disk.
Before using the ability to expand the VHD hard disk you must take the following issues into consideration:
Make sure no snapshots are associated with this VM.
Note: Expanding or extending partitions on Windows Vista and Windows Server 2008 is easier than on Windows Server 2003 or Windows XP, and is performed by using either the Disk Management snap-in from the Computer Management tool, or by using the DISKPART command. Please read my How to Extend a Disk Partition in Windows Vista and Server 2008 article for more information.
Next, after booting the VM, use Disk Management snap-in from the Computer Management tool, or by using the DISKPART command to expand the partition within Windows. While possible in Windows Server 2008 and Windows Vista, unfortunately, in Windows 2000/XP/2003, you cannot use the built-in tools to expand the System Partition (the one the Windows operating system is installed on). For these versions you will need to use of these free partition utilities.
Got a question? Post it on our Windows Server 2008 forums!