association
A class that contains two references that define a relationship between two
referenced objects.
asymmetric virtualization
A virtualization technique in which the virtualization engine is outside the
data path and performs a metadata-style service. The metadata server
contains all the mapping and locking tables while the storage devices
contain only data. See also symmetric virtualization.
auxiliary virtual disk
The virtual disk that contains a backup copy of the data and that is used in
disaster recovery scenarios. See also master virtual disk.
availability
The ability of a system to continue working, with perhaps a decrease in
performance, after individual components fail.
B
bandwidth
The range of frequencies an electronic system can transmit or receive. The
greater the bandwidth of a system, the more information the system can
transfer in a given period of time.
bitmap
A coded representation in which each bit, or group of bits, represents or
corresponds to an item; for example, a configuration of bits in main storage
in which each bit indicates whether a peripheral device or a storage block
is available or in which each group of bits corresponds to one pixel of a
display image.
blade One component in a system that is designed to accept some number of
components (blades). Blades could be individual servers that plug into a
multiprocessing system or individual port cards that add connectivity to a
switch. A blade is typically a hot-swappable hardware device.
block A unit of data storage on a disk drive.
block virtualization
The act of applying virtualization to one or more block-based (storage)
services for the purpose of providing a new aggregated, higher-level,
richer, simpler, or secure block service to clients. Block virtualization
functions can be nested. A disk drive, RAID system, or volume manager all
perform some form of block-address to (different) block-address mapping
or aggregation. See also virtualization.
Boolean
Pertaining to the processes used in the algebra formulated by George
Boole.
C
cache A high-speed memory or storage device used to reduce the effective time
required to read data from or write data to lower-speed memory or a
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.
Call Home
A communication service that links a machine to a service provider. The
164 IBM System Storage SAN Volume Controller: Hardware Installation Guide
To Next Page
Loading...
Need help?
General
