Qlogic 8200 Series, Руководство пользователя

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User’s Guide Converged Network Adapter
8200 and 3200 Series Adapters
Glossary-4 SN0054671-00 A
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.
PCIe (PCI Express)
A third-generation input/output (I/O)
standard that allows enhanced Ethernet
network performance beyond that of the
older peripheral component interconnect
(PCI) and PCI extended (PCI-x) desktop
and server slots.
port
Access points in a device where a link
attaches. The most common port types
are:
 N_Port is a Fibre Channel device port
that supports point-to-point topology.
 NL_Port is a Fibre Channel device port
that supports loop topology.
 F_Port is a port in a fabric where an
N_Port can attach.
 FL_Port is a port in a fabric where an
NL_Port can attach.
port instance
The number of the port in the system.
Each adapter may have one or multiple
ports, identified with regard to the adapter
as port 0, port 1 and so forth. to avoid
confusion when dealing with a system
containing numerous ports, each port is
assigned a port instance number when the
system boots up. So Port 0 on an adapter
might have a port instance number of, for
example, 8 if it is the eighth port discov-
ered by the system.
quality of service (QoS)
Methods used to prevent bottlenecks and
ensure business continuity when transmit-
ting data over virtual ports by setting priori-
ties and allocating bandwidth.
redundant array of
independent/inexpensive disks (RAID)
Fault-tolerant disks that look like either
single or multiple volumes to the server.
small computer systems interface (SCSI)
The original SCSI specification was a
hardware bus specification and a
packet-oriented protocol specification for
communicating on that bus. SCSI over
Fibre Channel uses the packet-oriented
protocol to communicate with storage
devices on the Fibre Channel.
storage area network (SAN)
Multiple storage units (disk drives) and
servers connected by networking topology.
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 LUNs.
A target is a device that responds to a
request 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.