Windows® 7 Virtual Hard Disk
Microsoft latest operating system, Windows 7, comes with a number of new features including relatively lesser known Virtual Hard Disk that enables a user to install various operating systems on a single machine.
The tool, which is a file formatted to be structurally identical to a physical Hard Disk Drive, enables you to test software on different operating systems and reduces the cost or hassle of actual hardware.
This feature allows a physical computer to mount and boot from an operating system contained within a VHD.
VHD’s ability to directly modify a virtual machine’s hard disk from a host server supports many applications, including:
- Life-cycle management and provisioning
- Backup and recovery
- Image management and patchingVHD
- Disk conversion (physical to virtual, and so on)
- Antivirus and security
- Moving files between a VHD and the host file system
Advantages of VHD
Multiple operating system support: Now you can easily install multiple operating system without making changes in Master Boot Record.
Backup-and-Restore: Changes to the contents of a VHD (such as infection by a virus, or accidental deletion of critical files) are easily undone.
Multi-User Isolation: Many current operating systems support having multiple users, but offer varying degrees of protection between them (e.g., one user of the OS could become infected by a virus which infects other users, or make changes to the OS which affect other users). By giving each user their own version of the operating system -- say, by creating for each of them a differencing VHD based on a base installation of the OS -- changes to any particular child image would have no effect on any of the other child images.