Network Management Overview; Fibre Channel Arbitrated Loop Protocol (Fc-Al) And Loop Initialization Primitive (Lip - Compaq Armada 6500 Hardware And Software Manual

The Hub 12 Management Utilities check the preset Community Names with
the ones on the managed device every time it starts so that a match is
guaranteed. The Community Names may have already been changed after
installation. If there is no match, the Hub 12 Management Utilities cannot
proceed.
IMPORTANT: Compaq Community Names are case-sensitive and limited to 15
characters.
Fibre Channel Arbitrated Loop Protocol
(FC-AL) and Loop Initialization Primitive
(LIP)
Most of todays SANs work in a physical and/or logical loop topography, and
the FC-AL protocol is the basic engine of the storage area network. Within the
FC-AL protocol system, using the Hub 12 Management Utilities, the
administrator can rely on necessary safeguards, called Loop Initialization
Primitives. LIPs serve the function of detecting and managing operating
failures among loop participants. Hub 12 Management Utilities assist in
determining the location of system problems.
Loop Initialization Primitives are special primitive signals that occur whenever
a new device is added or an old device is removed from the SAN. The LIPs
order devices attached to the SAN to briefly pause what they are doing, to
identify themselves, and to receive information about other connected
devices— in effect, performing a network initialization. These primitive
signals are necessary to the consistent performance of the system. There are
several basic types of LIPs, including LIP(F7,x) or LIP(F8,x).
LIPs are also the primary mechanisms to broadcast marginal loop operation by
a loop participant. If an element such as the optical detector within a loop
participant fails and can no longer act as a reliable repeater, it may broadcast a
LIP.
Network Management Overview A-5