Implement Fixed Hard Disk Image

[jhermsmeier]

A fixed hard disk image is a file that is allocated to the size of the virtual disk. For
example, if you create a virtual hard disk that is 2 GB in size, the system will create
a host file approximately 2 GB in size.

The space allocated for data is followed by a footer structure. The size of the entire
file is the size of the hard disk in the guest operating system plus the size of the
footer. Because of size limitations in the host file system, a fixed hard disk might be
limited. For example, on a FAT32 file system, the maximum size of the virtual hard
disk is 4 GB.

VHD Functions:

• Create
  (Creates a VHD image file, either using default parameters or using an existing virtual disk or physical disk)
• Compact
  (Reduces the size of a VHD backing store file)
• Expand
  (Increases the size of a fixed or dynamically expandable VHD)
• Mirror
  (Initiates a mirror operation for a virtual disk)
• Resize
  (Resizes a virtual disk)