Owner's manual

RAID ARAIDvolumeappears tothe operatingsystemtobeasingle logicaldisk.
RAI D improves performance by disk striping, which involves partitioning
each drive’s stora ge space into units. By placing data on multiple disks, I/O
operations can overlap in a balanced way, improving performance.
RAID 5-level data
storage
Provides data striping at the byte level and also stripe error correction
information. RAI D 5 congurations can tolerate one drive failure. Even with a
failed drive, thedatainaRAID 5volumecan stillbeaccessednormally.
redundancy In a redundant system, if you lose part of the system, it can continue to operate.
For example, if you have t wo power supplies with one that takes over if the other
one
dies, that’s redundancy.
serial ATA disk The evolution of the ATA (IDE) interface that changes the physical architecture
from parallel to serial and from master-slave to point-to-point. Unlike parallel
ATA interfaces that connect two drives; one congured as master, the other as
slave, each serial A TA drive is connected to its own interface.
simple network
management pro-
tocol (SNMP)
A widely used net work monitoring and control protocol. Data is passed from
SNMP agents, which are hardware and/or software processes reporting activity
in
each network device (hub, router, bridge, etc.) to the workstation console
used to oversee the network. The agents return information contained in a MI B
(Management Information Base) , which is a data structure that denes what is
obtainable from the device and what can be controlled (turned off, on, etc.).
small computer
systems interface
(SCSI)
A standard, intelligent parallel interface for attaching peripheral devices to
computers, based on a device independent protocol.
SMTP Simple Mail Transfer Protocol. A transmission control protocol/Internet protocol
(TCP/IP) protocol that allows theusertocreate, send,and receivetextmessages.
SMTP protocols specify how m essages are passed across a link from one system
to another. They do not specify how the mail application accepts, presents,
or
stores the mail.
storage pool Multiple disk arrays logically grouped together from which the dynamic disk le
system allocates storage. The disk arrays in a VLS are automatically con gured
into one storage array.
tape drive (1) A device that reads data from and writes data onto tape. (2) A software
emulation of a tape drive is called a virtual tape drive.
virtual library sys-
tem
(VLS)
A computer system that appears as a tape library to other systems on a network.
A
computer system that emulates a tape library.
virtual tape Also known as a piece of virtual media or a VLS cartridge. A disk d rive buffer
that
emulates one physical tape to the host system and appears to the host
backup application as a physical tape. The same application used to back up
to
tape is used, but the data is stored on disk. Data can be written to and read
from the virtual tape, and the virtual tape c an be migrated to physical tape.
virtual tape drive An emulation of a physical transport in a virtual tape librar y that looks like a
physical tape transport to the host backup application. The data written to the
virtual tape drive is really being written to disk. See also virtual tape library.
virtual tape library A disk drive buffer containing virtual tape and virtual tape drives. See also
virtual tape drive.
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Glossary