788 Implementing the IBM Storwize V7000 with IBM Spectrum Virtualize V8.2.1
Vital product data
Vital product data (VPD or VDP) is information that uniquely defines system, hardware, 
software, and microcode elements of a processing system.
Volume
A volume is an IBM Storwize V7000 logical device that appears to host systems that are 
attached to the SAN as a SCSI disk. Each volume is associated with exactly one I/O Group. A 
volume has a preferred node within the I/O Group.
Volume copy
A volume copy is a physical copy of the data that is stored on a volume. Mirrored volumes 
have two copies. Non-mirrored volumes have one copy.
Volume protection
To prevent active volumes or host mappings from inadvertent deletion, the system supports a 
global setting that prevents these objects from being deleted if the system detects that they 
have recent I/O activity. When you delete a volume, the system checks to verify whether it is 
part of a host mapping, FlashCopy mapping, or remote-copy relationship. In these cases, the 
system fails to delete the volume, unless the -force parameter is specified. Using the -force 
parameter can lead to unintentional deletions of volumes that are still active. Active means 
that the system detected recent I/O activity to the volume from any host.
Write-through mode
Write-through mode is a process in which data is written to a storage device at the same time 
that the data is cached.
Written capacity
See “Capacity” on page 771.