HP StorageWorks Disk Array XP operating system configuration guide: SGI IRIX (A5951-96075, December 2005)

DKU (disk cabinet
unit)
The array cabinets that house the disk array p hysical disks.
emulation modes The logical devices (LDEVs) associated with each RA ID group
are assigned an emulation mode that makes them operate like
OPEN system d
isk drives. The emulation mode determines the
size of an LDEV:
OPEN-3: 2.46 GB
OPEN-8: 7.38 G
B
OPEN-9: 7.42 GB
OPEN-E: 13.56 GB
OPEN-L: 36 GB
OPEN-V: User-defined custom size
failover Disconnecting a failed unit or path and replacing it with an
alternative unit or path in order to continue functioning.
FC Fibre
Channel.
FC-AL Fibre Channel arbitrated loop.
FCP Fibre Channel Protocol.
GB Gigabytes.
HBA Host bus adapter.
host mode Each port can be configuredforaparticularhosttype.These
modes are represented as two-digit hexadecimal numbers. For
example, host mode 08 represents an HP-UX host.
LDEV Logical device. An LDEV is created when a RAID group is
carved into pieces according to the selected host emulation
mode (that is, OPEN-3, OPEN-8, OPEN-L). The number of
resulting LDEVs depends on the selected emulation m od e. The
term LDEV is often used synonymously with the term volume.
LUN Logical unit number. A LUN results from mapping a SCSI
logical unit number, port ID, and LDEV ID to a RAID group.
The size of the LUN is determined by the emulation mode of
the LDEV and the number of LD EVs associated with the LU N.
For example, a LUN associated with t wo OPEN-3 LDEVs has a
size of 4,693 MB.
LUSE A LUN is normally associated with only a single LD EV. The
LUSE feature allows a LUN to be associated with 1 to 36
LDEVs. Essentially, LUSE makes it possible for applications
to access a single large p ool of storage. The LUSE feature
is available when the HP StorageWorks LUN Configuration
Manager product is installed.
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Glossary