IBM XSERIES 255 TYPE 8685, Hardware Maintenance Manual 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”
for more information.
v Diagnostic programs and error messages
The server diagnostic programs are stored in upgradeable read-only memory
(ROM) on the processor board. These programs are the primary method of
testing the major components of your server. See “Diagnostic programs and error
messages” on page 28 for more information.
v Light path diagnostics
Your server has light-emitting diodes (LEDs) to help you identify problems with
server components. These LEDs are part of the light path diagnostics that are
built into your server. By following the path of lights, you can quickly identify the
type of system error that occurred. See “Identifying problems using status LEDs”
on page 30 for more information.
v
Error symptoms
Other error symptoms, along with suggested steps to correct the problems, are
described at “Error symptoms” on page 138.
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 that are 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 your operating system or application program appears.
If POST detects a problem, more than one beep sounds, and an error message
appears on your screen. See “Beep symptoms” on page 127 and “POST error
codes” on page 146 for more information.
Notes:
1. If you have a power-on password or administrator password set, you must type
the password and press Enter, when prompted, before POST will continue.
2. 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.
The POST error log contains the three most recent error codes and messages that
the system generated during POST. The System Error log contains all messages
issued during POST and all system status messages from the service processor.
You can view the contents of the System Error log from the Configuration/Setup
Utility program or from the diagnostic programs.
Chapter 3. Diagnostics
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