Installation guide

ISR651103-00 C Glossary-5
iSR6152 Intelligent Storage Router
Installation Guide
load balancing
A software feature that improves system
performance by balancing device access
between multiple ports for maximum
resource efficiency.
loop initialization process
See LIP.
loopback
Diagnostic tool that routes transmit data
through a loopback connector back to the
same adapter.
LUN
Logical unit number, a subdivision of a
SCSI target. It is the small integer handle
that differentiates an individual disk drive
or partition (volume) within a common
SCSI target device such as a disk array.
A LUN can be a single physical disk drive,
multiple physical disk drives, or a portion
(volume) of a single physical disk drive.
However, LUNs are typically not entire disk
drives but rather virtual partitions
(volumes) of a RAID set.
Using LUNs, the Fibre Channel host can
address multiple peripheral devices that
may share a common controller.
maintenance button
Multifunction momentary switch on the
front panel of the router.
management workstation
PC workstation used to manage routers
remotely by connecting to the routers
using SANsurfer Router Manager or CLI
commands.
maximum transmission unit
See MTU.
media
Physical-layer information carriers. Fibre
Channel supports several different
physical media: copper, multimode optical,
and single-mode optical. All Fibre Channel
protocols are supported on all media.
MIB
Management information base. A set of
guidelines and definitions for SNMP
functions.
MTU
Maximum transmission unit. Refers to the
size (in bytes) of the largest packet (IP
datagram) that a specified layer of a
communications protocol can transfer.
N_Port
Node port. Connects by a point-to-point
link to either a single N_Port or a single
F_Port. N_Ports handle creation, detec-
tion, and flow of message units to and from
the connected systems. N_Ports are end
ports in virtual point-to-point links through
a fabric, for example N_Port to F_Port to
F_Port to N_Port using a single Fibre
Channel fabric switch. See also FL_Port.