HP StorageWorks 1000i Virtual Library System User Manual
Page 120

RAID
A RAID volume appears to the operating system to be a single logical disk.
RAID improves performance by disk striping, which involves partitioning
each drive’s storage 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. RAID 5 configurations can tolerate one drive failure. Even with a
failed drive, the data in a RAID 5 volume can still be accessed normally.
redundancy
In a redundant system, if you lose part of the system, it can continue to operate.
For example, if you have two 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 configured as master, the other as
slave, each serial ATA drive is connected to its own interface.
simple network
management pro
tocol (SNMP)
A widely used network 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 MIB
(Management Information Base), which is a data structure that defines 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 the user to create, send, and receive text messages.
SMTP protocols specify how messages 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 file
system allocates storage. The disk arrays in a VLS are automatically configured
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 drive 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 can be migrated to physical tape.
virtual tape drive
An emulation of a physical transport in a virtual tape library 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