IBM 7940, Problem Determination And Service Manual

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microprocessor socket. See “Microprocessor problems” on page 91 for
information about diagnosing microprocessor problems.
v Before you run the diagnostic programs, you must determine whether the failing
server is part of a shared hard disk drive cluster (two or more servers sharing
external storage devices). If it is part of a cluster, you can run all diagnostic
programs except the ones that test the storage unit (that is, a hard disk drive in
the storage unit) or the storage adapter that is attached to the storage unit. The
failing server might be part of a cluster if any of the following conditions is true:
– You have identified the failing server as part of a cluster (two or more servers
sharing external storage devices).
– One or more external storage units are attached to the failing server and at
least one of the attached storage units is also attached to another server or
unidentifiable device.
– One or more servers are located near the failing server.
Important: If the server is part of a shared hard disk drive cluster, run one test
at a time. Do not run any suite of tests, such as “quick” or “normal” tests,
because this might enable the hard disk drive diagnostic tests.
v If the server is halted and a POST error code is displayed, see “Error logs” on
page 76. If the server is halted and no error message is displayed, see
“Troubleshooting tables” on page 86 and “Solving undetermined problems” on
page 121.
v
For information about power-supply problems, see “Solving power problems” on
page 119.
v For intermittent problems, check the error log; see “Error logs” on page 76 and
“Diagnostic programs, messages, and error codes” on page 101.
Performing the checkout procedure
To perform the checkout procedure, complete the following steps:
1. Is the server part of a cluster?
v
No: Go to step 2.
v Yes: Shut down all failing servers that are related to the cluster. Go to step 2.
2. Complete the following steps:
a. Check the power supply LEDs, see “Power-supply LEDs” on page 99.
b. Turn off the server and all external devices.
c. Check all internal and external devices for compatibility at
http://www.ibm.com/servers/eservers/serverproven/compat/us/.
d. Check all cables and power cords.
e. Set all display controls to the middle positions.
f. Turn on all external devices.
g. Turn on the server. If the server does not start, see “Troubleshooting tables”
on page 86.
h. Check the system-error LED on the operator information panel. If it is
flashing, check the error LEDs (see “System board error LEDs and the light
path button” on page 98).
i. Check for the following results:
v Successful completion of POST (see “POST” on page 67 for more
information)
v
Successful completion of startup
3. Did one or more beeps sound?
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IBM System x3455 Type 7940 and 7941: Problem Determination and Service Guide