HP StorageWorks 2.128 SAN Director Switch - Manual (Page 161)

Fabric OS 5.x administrator guide 161
6. Check the results of the loopback test and proceed as follows:
• If the loopback test failed, the port is bad. Replace the port blade.
• If the loopback test did not fail, the SFP is bad.
7. Optional: To rule out cabling issues:
a. Insert a new cable into the suspected marginal port.
b. Issue the
portErrShow
command to determine whether a problem still exists.
• If the
portErrShow
output displays a normal number of generated errors, the issue is solved.
• If the
portErrShow
output still displays a high number of generated errors, follow the
troubleshooting procedures for the host or storage device.
Inaccurate information in the system message log
In rare instances, events gathered by the track change feature can report inaccurate information to the
system message log.
For example, consider a case where a user enters a correct user name and password, but the login is
rejected because the maximum number of users was reached. The system message log reports this login
as successful.
If the maximum number of switch users is reached, the switch still performs correctly in that it rejects the
login of additional users (even if they enter a correct user name and password).
However, in this limited example, the Track Change feature reports this event inaccurately to the system
message log and the login appears successful. This scenario occurs only when the maximum number of
users is reached; otherwise, the login information displayed in the system message log should reflect
reality.
For information regarding enabling and disabling TC, see ”
Tracking and controlling switch changes ” on
page 35.
Port initialization and FCP auto-discovery process
The steps in the port initialization process represent a protocol used to discover the type of connected
device and establish the port type. The possible port types are as follows:
• U_Port: Universal FC port. This port type is the base Fibre Channel port type and all unidentified or
uninitiated ports are listed as U_Ports.
• FL_Port: Fabric Loop port. This port connects both public and private loop devices.
• G_Port: Generic port. This port acts a transition port for non-loop fabric-capable devices (E_Port and
F_Port).
• E_Port: Expansion port. This port type is assigned to ISL links.
• F_Port: Fabric port. This port is assigned to fabric capable devices.
The FCP auto-discovery process enables private storage devices that accept PRLI to communicate in a
fabric.
If device probing is enabled, the embedded port logins (PLOGIs) and attempts a PRLI into the device to
retrieve information to enter into the Name Server. This enables private devices that do not FLOGI but
accept PRLI to be entered in the Name Server and receive full fabric citizenship. Private devices that
5 Internal (parallel) loopback (indicates no external
equipment)
7 Backend bypass and port loopback
8 Backend bypass and SERDES loopback
9 Backend bypass and internal loopback
Table 29 Loopback modes (continued)
Mode Description