HP 6400/8400 User Manual page 138

J
JBOD Just a Bunch of Disks.
L
laser A device that amplifies light waves and concentrates them in a narrow, very intense beam.
Last Fault View An HSV Controller display defining the last reported fault condition.
Last Termination See LTEA.
Error Array
license key A WWN-encoded sequence that is obtained from the license key fulfillment website.
link 1.
2.
logon A procedure whereby a user or network connection is identified as being an authorized network
user or participant.
loop See arbitrated loop.
loop ID Seven-bit values numbered contiguous from 0 to 126 decimal that represent the 127 valid AL-PA
values on a loop. (With Fibre Channel, not all 256 hexadecimal values are allowed as AL-PA
values.)
loop pair A Fibre Channel attachment between a controller and physical disk drives. Physical disk drives
connect to controllers through paired Fibre Channel arbitrated loops. There are two loop pairs,
designated loop pair 1 and loop pair 2. Each loop pair consists of two loops (called loop A and
loop B) that operate independently during normal operation, but provide mutual backup in case
one loop fails.
LTEA Last termination event array. A two-digit HSV Controller number that identifies a specific event
that terminated an operation. Valid numbers range from 00 to 31.
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.
M
management The HP P6000 Command View software that controls and monitors the HP Enterprise storage
agent system. The software can exist on more than one management server in a fabric. Each installation
is a management agent.
management A significant occurrence to or within the management agent software, or an initialized storage
agent event cell controlled or monitored by the management agent.
mean time See MTBF.
between failures
Mega A notation denoting a multiplier of 1 million (1,000,000).
metadata The data in the first sectors of a disk drive that the system uses to identify virtual disk members.
micro meter See µm.
mirrored caching A process in which half of each controller's write cache mirrors the companion controller's write
cache. The total memory available for cached write data is reduced by half, but the level of
protection is greater.
mirroring The act of creating an exact copy or image of data.
MTBF Mean time between failures. The average time from start of use to first failure in a large population
of identical systems, components, or devices.
multi-mode fiber A fiber optic cable with a diameter large enough (50 microns or more) to allow multiple streams
of light to travel different paths from the transmitter to the receiver. This transmission mode enables
bidirectional transmissions.
138 Glossary
A connection of ports on fibre channel devices.
A full duplex connection to a fabric or a simplex connection of loop devices.