IBM 5786, Процедуры снятия и замены

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Problem determination procedures
Problem determination procedures are provided by power-on self-tests (POSTs), service request numbers,
and maintenance analysis procedures (MAPs). Some of these procedures use the service aids that are
described in the user or maintenance information for your system SCSI attachment.
Disk drive module power-on self-tests
The disk drive module Power-on Self-Tests (POSTs) start each time that the module is switched on, or
when a Send Diagnostic command is received. They check whether the disk drive module is working
correctly. The POSTs also help verify a repair after a Field Replaceable Unit (FRU) has been exchanged.
The tests are POST-1 and POST-2.
POST-1 runs immediately after the power-on reset line goes inactive, and before the disk drive module
motor starts. POST-1 includes the following tests:
v
Microprocessor
v ROM
v
Checking circuits
If POST-1 completes successfully, POST-2 is enabled.
If POST-1 fails, the disk drive module is not configured into the system.
POST-2 runs after the disk drive module motor has started. POST-2 includes the following tests:
v
Motor control
v
Servo control
v
Read and write on the diagnostic cylinder (repeated for all heads)
v Error checking and correction (ECC).
If POST-2 completes successfully, the disk drive module is ready for use with the system.
If POST-2 fails, the disk drive module is not configured into the system.
SCSI card power-on self-tests
The SCSI card Power-On Self Tests (POSTs) start each time power is switched on, or when a Reset
command is sent from the using system SCSI attachment. They check only the internal components of the
SCSI card; they do not check any interfaces to other FRUs.
If the POSTs complete successfully, control passes to the functional microcode of the SCSI card. This
microcode checks all the internal interfaces of the I/O enclosure, and reports failures to the host system.
If the POSTs fail, one of the following events occur:
v
The SCSI card check LED and the enclosure check LED come on.
v
If the SCSI was configured for high availability using a dual initiator card the error will be reported.
However, the functional operation of the enclosure is not affected. For example, the customer still has
access to all the disk drive modules.
The failure is reported when:
© Copyright IBM Corp. 2010
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