HP StorageWorks XP24000/XP20000 Disk Array Site Preparation Guide (AE002-96055, September 2010)

are numbered sequentially. The disk array supports a certain number of CUs,
depending on the disk array model. Each CU can manage multiple LDEVs.
Therefore, to uniquely identify a particular LDEV requires both the CU number
and the LDEV number.
CS Critical Support.
CSR Customer self repair.
CU Control unit.
CVS Custom volume size. CVS devices (OPEN-x CVS) are custom volumes configured
using array management software to be smaller than normal fixed-size OPEN
system volumes. Synonymous with volume size customization (VSC).
disk group A named group of disks selected from all the available disks in a disk array.
One or more virtual disks can be created from a disk group. Also refers to the
physical disk locations associated with a parity group.
disk type The manufacturing ID written into the physical disk controller firmware. In most
cases, the disk type is identical to the disk model number.
DKA Disk adapter.
DKC Disk controller.
DKU Disk cabinet unit. The array cabinet that houses the physical disks.
DRR Disk recovery and restore unit. The unit responsible for data recovery and
restoration in the event of a cache failure.
emulation mode The LDEVs associated with each RAID group are assigned an emulation mode
that makes them operate like OPEN system disk drives. The emulation mode
determines the size of an LDEV.
OPEN-3: 2.46 GB
OPEN-8: 7.38 GB
OPEN-9: 7.42 GB
OPEN-E: 13.56 GB
OPEN-K: Not available
OPEN-L: 36 GB
OPEN-M Not available
OPEN-V: User-defined custom size
EPO Emergency power-off.
ESCON Enterprise systems connection An optical interface used to connect the mainframe
to the control unit; a predecessor to FICON.
ESD Electrostatic discharge. The emission of a potentially harmful static electric voltage
as a result of improper grounding.
expanded LUN A LUN is normally associated with only a single LDEV. The LUN Size Expansion
(LUSE) feature allows a LUN to be associated with 2-36 LDEVs. Essentially, LUSE
makes it possible for applications to access a single large pool of storage. LUSE
is an optional feature.
ExSA Extended serial adapter.
Glossary70