Before adding or generally managing cache devices, you should understand the prerequisites and limitations. You should also refer to the related prerequisites and limitations when adding a file system.
The NAS Bridge virtual machine is assigned a set of resources, including virtual hard drives. You must have a virtual hard drive available for each cache device. When you create a cache device, you must associate it with a specific virtual machine hard drive. The actual physical drive can be a local drive, or a remote NAS or SAN drive.