Qlogic QLA2 Series, User Manual

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SANsurfer FC/CNA HBA CLI User’s Guide
Command Line Interface for QLogic FC and FCoE Adapters
Glossary-2 SN0054614-00 K
boot device
The device, usually the hard disk, that
contains the operating system the BIOS
uses to boot from when the computer is
started.
cache
A temporary high-speed storage (memory)
area where recently used or frequently
accessed data is stored for rapid access,
thus increasing the efficiency of processor
operations.
Cache contents duplicate recently-used
values stored on disk or elsewhere. Cache
is quick to access relative to the original
data, which either takes more time due to
slow disc-access time, or is slow to
compute. After data is stored in the cache,
future use can be made by accessing the
cached copy rather than re-finding or
recomputing the original data, so that the
average access time is lower.
„ L1 cache —Primary (smallest) cache
on the same chip as the processor.
„ L2 cache —Secondary (larger) cache.
Either on the processor chip or
external to the processor.
class of service
See CoS .
CNA
Converged network adapters support both
data networking (TCP/IP) and storage
networking (FC) traffic on a single I/O
adapter using two new technologies:
Enhanced Ethernet and Fibre Channel
over Ethernet ( FCoE ).
converged network adapter
See CNA .
CoS
Class of service (CoS) is a 3-bit field within
a layer two Ethernet frame header when
using IEEE 802.1Q. It specifies a priority
value of between 0 (signifying best-effort)
and 7 (signifying priority real-time data)
that can be used by quality of service disci-
plines to differentiate traffic.
CoS is a way of managing traffic in a
network by grouping similar types of traffic
(for example, e-mail, streaming video,
voice, large document file transfer)
together and treating each type as a class
with its own level of service priority.
Fibre Channel classes of service include
Class 1, 2, 3, 4, and 6.
CSV file
A comma separated values file. A data file
used for storage of data structured in a
table form. Each line in the file corre-
sponds to a row in the table. Within a line,
fields are separated by commas, each field
belonging to one table column.
data center bridging
See DCB .
data center bridging exchange protocol
See device .
data center Ethernet
See DCE .
DCE
Data center Ethernet (DCE) is a Cisco
term that refers to enhancements to
Ethernet bridges that enables LAN and
SAN connectivity over an Ethernet
network. The acronym DCE is a Cisco
trademark. The enhancements described
within Cisco Data Center Ethernet helped
create the IEEE 802.1 Data Center
Bridging working group (DCB).