Capturing machine state for a physical system requires intelligent backup software with routines to coordinate data state and hooks to quiesce applications. Software that backs up the operating system and other protected components also needs special privileges. Restoring machine state to a physical system demands even more effort, often involving “bare metal” operations that require taking the system completely offline. In other words, the applications that back up the state of a physical machine also rely on the state of that machine, and applications that restore an earlier state of a machine need the machine to have effectively no state. As you can imagine (or have experienced), physical machine backup and restore operations frequently encounter failures ranging from nuisances to catastrophes. In the best cases, they add significant time delays. As a result, most administrators treat physical machine restoration as an emergency recovery procedure, not something for their daily toolkit.