HP 6400.8400 Enterprise Virtual Array - Manual (Page 143)

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.
Network Storage
Controller See NSC.
node port A device port that can operate on the arbitrated loop topology.
non-OFC (Open
Fibre Control) A laser transceiver whose lower-intensity output does not require special open Fibre Channel
mechanisms for eye protection. The HP Enterprise Storage System transceivers are non-OFC
compatible.
NONCRITICAL
Condition An EMU condition that occurs when one or more elements in the drive enclosure fail or are
operating outside specifications. The failure does not affect operation of the enclosure; all devices
in the enclosure continue to operate according to specifications. If there are additional failures,
however, the devices may not operate properly. UNRECOVERABLE and CRITICAL errors take
precedence over this condition. This condition takes precedence over the INFORMATION
condition. Early correction can prevent the loss of data.
NSC Network storage controller. The HSV controllers used by the HP Enterprise Storage System.
NVRAM Nonvolatile Random Access Memory. Memory whose contents are not lost when a system is
turned Off or if there is a power failure. This is achieved through the use of UPS batteries or
implementation technology such as flash memory. NVRAM is commonly used to store important
configuration parameters.
O
occupancy alarm
level A percentage of the total disk group capacity in blocks. When the number of blocks in the disk
group that contain user data reaches this level, an event code is generated. The alarm level is
specified by the user.
OCP Operator Control Panel. The element that displays the controller’s status using indicators and an
LCD. Information selection and data entry is controlled by the OCP pushbutton.
online storage An allotment of storage space that is available for immediate use, such as a peripheral device
that is turned on and connected to a server.
operator control
panel See OCP.
P
param That portion of the HP HSV controller termination code display that defines:
•
The two-character parameter identifier that is a decimal number in the 0 through 31 range.
•
The eight-character parameter code that is a hexadecimal number.
password A security interlock where the purpose is to allow:
•
A management agent to control only certain storage systems
•
Only certain management agents to control a storage system
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