Logical disks may be just a single disk, part of a volumeset,
 	part of a stripeset, part of a host-based shadowset, part of
 	a host-based raid set or any combination.

 	The file to be used for the logical disk may be placed on any
 	physical disk, in any directory. A backup can be made to protect
 	the disk.

 	A physical device may be 'replaced' by a logical disk to enable
 	logging of all I/O of the physical disk (See CONNECT/REPLACE).