Phoenix RPC12 Series, Справочное руководство CLI

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3 Phoenix RPC12 Series CLI Reference Manual • September 2008
broadcast write Technology that provides simultaneous caching of write data to both
RAID controllers’ cache memory with positive direct memory access
acknowledgement (certified DMA).
cache A high speed memory or storage device used to reduce the effective
time required to read data from or write data to a lower speed memory
or device. Read cache holds data in anticipation that it will be requested
by a client. Write cache holds data written by a client until it can be
safely stored on more permanent storage media such as disk or tape.
(SNIA)
See also write-back cache , write-through cache .
capacitor pack The controller module component that provides backup power to
transfer unwritten data from cache to Compact Flash memory in the
event of a power failure. Storing the data in Compact Flash provides
unlimited backup time. The unwritten data can be committed to the disk
drives when power is restored.
CAPI
Phoenix
Configuration API.
channel A physical path used for the transfer of data and control information
between storage devices and a RAID controller or a host; or, a SCSI
bus in a controller module. The terms channel and port are used
interchangeably within the user interfaces.
chassis An enclosure’s metal housing.
chunk size The number of contiguous blocks in a stripe on a disk drive in a virtual
disk. The number can be adjusted to improve performance. Generally,
larger chunks are more effective for sequential reads. See
block .
CLI The command-line interface that system administrators can use to
configure, monitor, and manage Phoenix storage systems. The CLI is
accessible from any management host that can access a controller
module through an out-of-band Ethernet or RS-232 connection.
controller The control logic in a storage subsystem that performs command
transformation and routing, aggregation (RAID, mirroring, striping, or
other), high-level error recovery, and performance optimization for
multiple storage devices. (SNIA)
A controller is also referred to as a RAID controller.
controller enclosure An enclosure that contains disk drives and one or two controller
modules. See
controller module .