HP StorageWorks 1000i Virtual Library System User Manual
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iSCSI
Pronounced "eye-scuzzy", an acronym for Small Computer System Interface
protocol over IP network instead of a direct SCSI compatible cable which
enables data blocks to be read from or sent at high speed to a storage device
such as a disk or tape drive
LAN
A local area network (LAN) is a group of computers and associated devices that
share a common communications line or wireless link and typically share the
resources of a single processor or server within a small geographic area (for
example, within an office building).
library
A storage device that handles multiple units of media and provides one or more
drives for reading and writing them, such as a physical tape library and virtual
tape library. Software emulation of a physical tape library is called a virtual
tape library. See also virtual tape library.
logical unit num
ber (LUN)
An address used in the SCSI protocol to access a device within a target. In the
case of the VLS, a LUN is assigned to each virtual library and tape drive.
LUN mapping
A mechanism of changing the LUN assignments for a specific host.
LUN masking
An authorization process that makes a LUN available to some hosts and
unavailable to other hosts.
master server
A computer that provides administration and control for backup and restore
operations for all clients and servers in a master and media server cluster.
mean time until
data loss (MTDL)
The average time until a component failure can be expected to cause data loss.
This includes the consideration that RAID redundancy can protect against data
loss from the failure of a single component.
media access con
trol (MAC) address
A low-level unique hardware identifier for every Ethernet port in the world that
is physically stored inside a network card or similar network interface. MAC
addresses are assigned by the IEEE.
media server
A computer whose purpose is to move or copy data from one location to
another, such as from network clients to tape cartridges in a library.
MTBF
Mean Time Between Failures. A statistic that predicts how often failures will
occur.
node
In networks, a processing location. A node can be a computer or some other
device, such as a printer. Every node has a unique network address.
oversubscription
A condition that exists when more virtual media storage is configured on a
VLS than there is physical storage available. Because the VLS dynamically
allocates storage space as user data is written, the VLS allows you to allocate
more storage for virtual media than is physically available.
port mapping
A mechanism of assigning a LUN (virtual device), such as a virtual library or
tape drive, to a specific Fibre Channel host port. Port mapping allows you
to load-balance the LUNs among the Fibre Channel host ports to maximize
bandwidth. At this time, you must manually load-balance the virtual tape drives
in a VLS.
power supply
The computer component that supplies power to a computer. Most personal
computers can be plugged into standard electrical outlets. The power supply
then pulls the required amount of electricity and converts the AC current to DC
current. It also regulates the voltage to eliminate spikes and surges common in
most electrical systems.
processor
The part of a computer (a microprocessor chip) that does most of the data
processing; the CPU and the memory form the central part of a computer to
which the peripherals are attached.
HP StorageWorks 1000i Virtual Library System
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