Unlike its predecessors, Windows Server 2008 R2 allows the operating system to treat a VHD file almost exactly like a physical disk. Windows 7 and Windows Server 2008 R2 Boot from VHD
The most transformative feature introduced in Windows Server 2008 R2 was the ability to natively mount a VHD directly within the host operating system—without needing a hypervisor. Through the Disk Management console or simple PowerShell commands, an administrator could attach a .vhd file, which would then appear to the system as a physical disk, complete with drive letters and full file system access. This capability revolutionized several common administrative tasks. For instance, file-level recovery from a virtual machine’s hard drive became instantaneous; instead of booting a failed VM, an admin could mount its VHD, copy a single corrupted document, and dismount it. Similarly, offline servicing of virtual machines—patching an image, updating antivirus definitions, or modifying registry keys—could be performed safely while the VM was powered off. This seamless integration erased the artificial boundary between the virtual and physical storage worlds. windows server 2008 r2 vhd