IBM 88371RU, Maintenance And Troubleshooting Manual

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Diagnostic tools overview
The following tools are available to help you identify and resolve hardware-related
problems:
v
POST beep codes, error messages, and error logs
The power-on self-test (POST) generates beep codes and messages to indicate
successful test completion or the detection of a problem (see “POST error logs”).
The POST error log contains the three most recent error codes and messages
that the system has generated during POST.
The system-error log contains all the error messages that were issued during
POST.
Note: The system-error log on the xSeries 336 server is available only with the
Remote Supervisor Adapter II SlimLine.
v Diagnostic programs and error messages
The server diagnostic programs, stored in upgradable read-only memory (ROM)
on the system board, are the primary method of testing the major components of
the server (see “Diagnostic programs, error codes, and messages” on page 70).
v
ServerGuide error symptoms
ServerGuide error symptoms are described at “ServerGuide error symptoms” on
page 110.
v
SCSI error messages
For information on SCSI errors, see “Small computer system interface messages”
on page 72 and “SCSI error codes” on page 115.
v
Light path diagnostics
The server has light-emitting diodes (LEDs) to help you identify problems with
server components. By following the light path, you can identify the type of
problem that occurred. The light path begins with the LEDs on the operator
information panel (see “Light path diagnostics” on page 73).
v Error symptom tables
These tables list problem symptoms, along with suggested steps to correct the
problems (see the “Error symptoms” on page 103).
POST error logs
When you turn on the server, it performs a series of tests to check the operation of
server components and some of the options installed in the server. This series of
tests is called the power-on self-test, or POST.
If POST finishes without detecting any problems, a single beep sounds, and the first
screen of the operating system or application program appears.
If POST detects a problem, more than one beep sounds, an error message appears
on the screen, or both (see “Beep symptoms” on page 84 and “POST error codes”
on page 88).
Note: A single problem might cause several error messages. When this occurs,
work to correct the cause of the first error message. After you correct the
cause of the first error message, the other error messages usually will not
occur the next time you run the test.
Chapter 5. Diagnostics
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