HP EVA P6000, Руководство пользователя

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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 (not all 256 hexadecimal values are allowed as AL_PA values per Fibre Channel).
loop pair A Fibre Channel attachment 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. The valid numbers range from 00 to 47.
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
agent The HP P6000 Command View 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 A significant occurrence to or within the management agent software, or an initialized storage
cell controlled or monitored by the management agent.
management
server A server on which management software is installed, such as HP P6000 Command View and
HP Replication Solutions Manager.
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 MB .
Mb Megabit. A term defining a data transfer rate.
See also
Mbps .
MBps Megabytes per second. A measure of bandwidth or data transfers occurring at a rate of
1,000,000 (10
6
) bytes per second.
Mbps Megabits per second. A measure of bandwidth or data transfers occurring at a rate of 1,000,000
(10
6
) bits per second.
mean time
between failures See MTBF .
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.
N
near-online
storage On-site storage of data on media that takes slightly longer to access than online storage kept on
high-speed disk drives.
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