IBM TotalStorage SAN Volume Controller Installation Manual page 111

I/O group
A collection of virtual disks (VDisks) and node relationships that present a
common interface to host systems.
L
local fabric
In SAN Volume Controller, those storage area network (SAN) components
(such as switches and cables) that connect the components (nodes, hosts,
switches) of the local cluster together.
logical unit (LU)
An entity to which Small Computer System Interface (SCSI) commands are
addressed, such as a virtual disk (VDisk) or managed disk (MDisk).
logical unit number (LUN)
The SCSI identifier of a logical unit within a target. (S)
LU See logical unit.
LUN See logical unit number.
M
managed disk (MDisk)
A Small Computer System Interface (SCSI) logical unit that a redundant
array of independent disks (RAID) controller provides and a cluster
manages. The MDisk is not visible to host systems on the storage area
network (SAN).
managed disk group
A collection of managed disks (MDisks) that, as a unit, contain all the data
for a specified set of virtual disks (VDisks).
mapping
See FlashCopy mapping.
MDisk See managed disk.
N
node One SAN Volume Controller. Each node provides virtualization, cache, and
Copy Services to the storage area network (SAN).
O
object In object-oriented design or programming, a concrete realization of a class
that consists of data and the operations associated with that data.
offline Pertaining to the operation of a functional unit or device that is not under
the continual control of the system or of a host.
online Pertaining to the operation of a functional unit or device that is under the
continual control of the system or of a host.
P
port The physical entity within a host, SAN Volume Controller, or disk controller
system that performs the data communication (transmitting and receiving)
over the fibre channel.
81
Glossary