HP 316095-B21 - StorageWorks Edge Switch 2/24 Manual page 25

loop
A loop is a configuration of devices connected to the fabric via a fabric loop port (FL_Port)
interface card.
loop initialization primitive
(LIP) — In an arbitrated loop device, a process by which devices connected to hub ports
(H_Ports) on the arbitrated loop device notify other devices and the switch of their presence in
the loop by sending LIP sequences and subsequent frames through the loop. This process allows
linked arbitrated loop devices to perform fabric loop port (FL_Port) arbitration as they link
through hub ports.
loop master
In an arbitrated loop device, a reference to the loop master World Wide Name (WWN) field in
the Loop View, the loop master is the arbitrated loop device that is responsible for allocating
arbitrated loop physical addresses (AL-PAs) on the loop. An arbitrated loop device becomes the
loop master through arbitration when there are multiple arbitrated loop devices on the loop. The
arbitrated loop device with the lowest WWN becomes the loop master.
loop port
L_Port. Synonym for
loop switches
Loop switches support node loop port (NL_Port) Fibre Channel protocols. Switches sold as
loop support but upgradeable to fabric switches recounted as loop switches.
loopback plug
In a fiber optic environment, a type of duplex connector used to wrap the optical output signal
of a device directly to the optical input.
loopback test
Test that checks attachment or control unit circuitry, without checking the mechanism itself, by
returning the output of the mechanism as input.
LUN
See logical unit number.
MAC address
See Media Access Control
maintenance analysis procedure
(MAP) — A set of procedures that guide maintenance personnel through step-by-step
instructions for hardware fault isolation, repair, and verification.
maintenance port
Connector on the director where a PC running an ASCII terminal emulator can be attached or a
dial-up connection can be made for specialized maintenance support.
Directors and Edge Switches Glossary
hub port.
address.
Glossary
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