A coworker of mine recently pointed out that with Hyper-V and VHD's or VHDX's, expanding them is an offline operation. I have no reason to doubt him, I even looked it up myself and it does indeed appear to be the case, even in Server 2012. My question is, first, how in the world can Microsoft claim to compete with VMware given this massive shortcoming? Second, how does one work around that? Just create huge VHD's to begin with and hope you don't outgrow them, or if you do, hope that it's a server you can take offline to grow or wait until a scheduled outage to grow it? Seems like a very basic operation that has been in VMware for years... why isn't it possible in Hyper-V?