HP 6400.8400 Enterprise Virtual Array - Manual (Page 139)

disk migration
state A physical disk drive operating state. A physical disk drive can be in a stable or migration state:
Stable—The state in which the physical disk drive has no failure nor is a failure predicted.
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Migration—The state in which the disk drive is failing, or failure is predicted to be imminent.
Data is then moved off the disk onto other disk drives in the same disk group.
disk replacement
delay The time that elapses between a drive failure and when the controller starts searching for spare
disk space. Drive replacement seldom starts immediately in case the “failure” was a glitch or
temporary condition.
DR group failover An operation that reverses data replication direction so that the destination becomes the source
and the source becomes the destination. Failovers can be planned or unplanned and can occur
between DR groups or managed sets (which are sets of DR groups).
drive enclosure
event A significant operational occurrence involving a hardware or software component in the drive
enclosure. The drive enclosure EMU reports these events to the controller for processing.
dual fabric Two independent fabrics providing multipath connections between Fibre Channel end devices.
dual power supply
configuration See redundant power configuration.
dual-loop A configuration where each drive is connected to a pair of controllers through two loops. These
two Fibre Channel loops constitute a loop pair.
dynamic capacity
expansion A storage system feature that provides the ability to increase the size of an existing virtual disk.
Before using this feature, you must ensure that your operating system supports capacity expansion
of a virtual disk (or LUN).
E
EIA Electronic Industries Alliance. A standards organization specializing in the electrical and functional
characteristics of interface equipment.
EIP Event Information Packet. The event information packet is an HSV element hexadecimal character
display that defines how an event was detected. Also called the EIP type.
electromagnetic
interference See EMI.
electrostatic
discharge See ESD.
element In a disk enclosure, a device such as a, power supply, disk, fan/blower, or I/O module. The
object can be controllled, interrogated, or described by the enclosure services process.
EMI Electromagnetic Interference. The impairment of a signal by an electromagnetic disturbance.
EMU Environmental Monitoring Unit. An element which monitors the status of an enclosure, including
the power, air temperature, and blower status. The EMU detects problems and displays and
reports these conditions to a user and the controller. In some cases, the EMU implements corrective
action.
enclosure A unit used to hold various storage system devices such as disk drives, controllers, power supplies,
I/O modules, or fans/blowers.
enclosure address
bus An Enterprise storage system bus that interconnects and identifies controller enclosures and disk
drive enclosures by their physical location. Enclosures within a reporting group can exchange
environmental data. This bus uses enclosure ID expansion cables to assign enclosure numbers to
each enclosure. Communications over this bus do not involve the Fibre Channel drive enclosure
bus and are, therefore, classified as out-of-band communications.
enclosure number
(En) One of the vertical rack-mounting positions where the enclosure is located. The positions are
numbered sequentially in decimal numbers starting from the bottom of the cabinet. Each disk
enclosure has its own enclosure number. A controller pair shares an enclosure number. If the
system has an expansion rack, the enclosures in the expansion rack are numbered from 15 to
24, starting at the bottom.
enclosure services Those services that establish the mechanical environmental, electrical environmental, and external
indicators and controls for the proper operation and maintenance of devices with an enclosure
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