HP 3000 Enterprise Virtual Array - Manual (Page 152)

logon Also called login, it is 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 contiguously from 0 to 126 decimal and represent
the 127 valid AL_PA values on a loop (not all 256 hexadecimal values are
allowed as AL_PA values per Fibre Channel).
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 SCSI convention used to identify elements. The host
sees a virtual disk as a LUN. The LUN address a user assigns to a virtual disk for
a particular host will be the LUN at which that host will see the virtual disk.
management
agent
The HP Command View EVA software that controls and monitors the Enterprise
storage system. The software can exist on more than one management server in
a fabric. Each installation is a management agent.
management
agent event
Significant occurrence to or within the management agent software, or an
initialized storage cell controlled or monitored by the management agent.
Mb Megabit. A term defining a data transfer rate.
See also Mbps .
MB Megabtye. A term defining either:
• A data transfer rate.
• A measure of either storage or memory capacity of 1,048,576 (2 20 ) bytes.
See also MBps .
Mbps Megabits per second. A measure of bandwidth or data transfers occurring at a
rate of 1,000,000 (10 6 ) bits per second.
MBps Megabytes per second. A measure of bandwidth or data transfers occurring at
a rate of 1,000,000 (10 6 ) bytes per second.
mean time be-
tween failures
See MTBF .
Mega A notation denoting a multiplier of 1 million (1,000,000).
metadata Information that a controller pair writes on the disk array. This information is
used to control and monitor the array and is not readable by the host.
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.
152 Glossary