When you install and configure a server operating system, you hope you'll never have to do it again. It's inordinately complex and time-consuming. Each server is a unique creation, and each configuration meticulously adapted to a particular use.

Any installed drivers, applications and other software components reflect that specialized use. Even individual applications may have a unique set of patches. It's difficult, if not impossible, to identify each unique configuration and determine how to replicate it on a new OS.