HP XP20000/XP24000 Manual page 71

failover Disconnecting a failed unit or path and replacing it with an alternative unit or
path in order to continue functioning.
FAN Factory Authorization.
FC Fibre Channel. A network technology primarily used for storage networks.
FC-AL Fibre Channel arbitrated loop.
FCP Fibre Channel Protocol.
fence level A method of setting rejection of P9000 or XP Continuous Access write I/O
requests from the host according to the condition of mirroring consistency.
FICON Fibre connectivity. Hardware that connects the mainframe to the control unit.
GLM Gigabit link module. A 1 Gb/s fiber optic transceiver.
HA High availability.
HBA Host bus adapter. A built-in function or a card installed in a PC or other host
computer to enable connection of the host to the SAN.
HDD Hard disk drive.
host mode Each port can be configured for a particular host type. These modes are
represented as two-digit hexadecimal numbers. For example, host mode 08
represents an HP-UX host.
hot standby The act of using one or more servers (or disks) as a standby in case of a primary
server (disk) failure.
LD, 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-9). The number of resulting LDEVs depends on the selected emulation
mode. The term LDEV is also known as term volume.
local disk A disk in the host.
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 LDEVs associated with the LUN.
For example, a LUN associated with two OPEN-3 LDEVs has a size of 4,693
MB.
LUSE Logical Unit Size Expansion. The LUSE feature is available when the HP
StorageWorks LUN Manager product is installed, and allows a LUN, normally
associated with only a single LDEV, to be associated with 1 to 36 LDEVs.
Essentially, LUSE makes it possible for applications to access a single large pool
of storage.
MCU Main control unit.
MCS Mission Critical Services.
MIX A circuit board in the disk control unit that includes disk adapters and channel
adapters for interfacing disk drives and the host to cache memory.
XP24000/XP20000 Disk Array Site Preparation Guide 71