3PAR InForm® OS 2.3.1 Concepts Guide (320-200112 Rev B, February 2010)

GL 14
Glossary
InForm OS Version 2.3.1 3PAR InForm OS Concepts Guide
VLUN
Stands for virtual-LUN. A VLUN is a virtual
volume-LUN pairing expressed as either an active
VLUN or as a VLUN template. See also active
VLUN, VLUN template.
VLUN template
A rule that sets up the association between the
name of the virtual volume and a LUN-host, LUN-
port, or LUN-host-port combination. The three
types of VLUN templates are host-sees, port-
presents, and matched-set. See also active VLUN,
LUN.
VV
See virtual volume.
VV template
Virtual volume template. The template contains
a set of virtual volume parameters that can be
applied again and again to create volumes with
the same characteristics using the InForm
Management Console.
W
World-Wide Name (WWN)
A unique 64-bit value used to identify Fibre
channel devices on an arbitrated loop. The WWN
consists of a prefix issued by the IEEE to uniquely
identify the company and a suffix that is issued
by the company.
write-through mode
A caching technique in which the completion of
a write request is not signaled until data is safely
stored. Write performance with a write-through
cache is approximately that of a non-cached
system, but if the data written is also held in
cache, subsequent read performance may be
dramatically improved.
WWN
See World-Wide Name.
Z
zero fill
To fill unused storage space with the
representation of the character denoting “0”.
zone
A unit of physical disk space reserved by a
controller node for snapshot or snapshot
administration data. A single zone may occupy
space on more than one disk.