Qlogic Data Migration Service, Руководство пользователя

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ISR654606-00 A Glossary-3
Data Migration Service for HP StorageWorks MPX200
User’s Guide
path
A path to a device is a combination of an
adapter port instance and a target port as
distinct from internal paths in the fabric
network. A fabric network appears to the
operating system as an opaque network
between the adapter (initiator) and the
target.
Because a path is a combination of an
adapter and a target port, it is distinct from
another path if it is accessed through a
different adapter or it is accessing a
different target port. Consequently, when
switching from one path to another, the
driver might be selecting a different
adapter (initiator), a different target port, or
both.
This is important to the driver when
selecting the proper method of failover
notification. It can make a difference to the
target device, which might have to take
different actions when receiving retries of
the request from another initiator or on a
different port.
RAID
Redundant array of independent/inexpen-
sive disks. RAID technology groups
separate disks into one logical storage unit
(LUN) to improve reliability and/or perfor-
mance.
redundant array of
independent/inexpensive disks
See RAID .
SAN
Storage area network. Multiple storage
units (disk drives) and servers connected
by networking topology.
SCSI
Small computer system interface. A
high-speed interface used to connect
devices, such as hard drives, CD drives,
printers, and scanners, to a computer. The
SCSI can connect many devices using a
single controller. Each device is accessed
by an individual identification number on
the SCSI controller bus.
Secure shell
See SSH .
small computer system interface
See SCSI .
SSH
Secure shell. Protocol that secures
connections to the switch for the command
line interface.
storage area network
See SAN .
target
The storage-device endpoint of a SCSI
session. Initiators request data from
targets (usually disk-drives, tape-drives, or
other media devices). Typically, a SCSI
peripheral device is the target but an
adapter may, in some cases, be a target. A
target can contain many
LUN s.
A target is a device that responds to a
requested by an initiator (the host system).
Peripherals are targets, but for some
commands (for example, a SCSI COPY
command), the peripheral may act as an
initiator.