Virtualization is showing up in all layers of the storage infrastructure. Host, network and storage system-based block virtualization can each simplify volume management, ease data migrations and decrease storage provisioning times, but all of them increase the complexity of managing a storage environment. As the storage infrastructure becomes more abstracted, organizations may no longer be able to confidently pinpoint what data resides on what storage device or how to isolate the root cause of problems.

Where to embed virtualization and when to use it depends on the size of the infrastructure, the type of apps running in it, and the levels of control and visibility required by admins.