Why Hyper-V VHD Files Are So Large – And How To Efficiently Copy Them
Interesting blog post covering a tool to copy VHD files.The tool was created by a Microsoft MVP.
Details at https://blogs.technet.com/wchomak/archive/2010/03/31/why-hyper-v-vhd-files-are-so-large-and-how-to-efficiently-copy-them.aspx