IBM R/S6000 7012 300 Series Operator's Manual page 90

SCSI Bus Analyzer
This service aid provides a means to diagnose a SCSI Bus problem in a free–lance mode.
Prior to version 4.2 the SCSI Bus Service Aid was accessed via the SCSI Bus selection
from the Service Aid Selection Menu. Beginning with version 4.2 the SCSI Bus Service Aid
is accessed via the SCSI Bus Analyzer option from the Task Selection Menu.
To use this service aid, the user should have an understanding of how a SCSI Bus works.
This service aid should be used when the diagnostics cannot communicate with anything on
the SCSI Bus and cannot isolate the problem. Normally the procedure for finding a problem
on the SCSI Bus with this service aid is to start with a single device attached, ensure that it
is working, then start adding additional devices and cables to the bus ensuring that each
one works. This service aid will work with any valid SCSI Bus configuration.
The SCSI Bus Service Aid transmits a SCSI Inquiry command to a selectable SCSI
Address. The service aid then waits for a response. If no response is received within a
defined amount of time, the service aid will display a timeout message. If an error occurs or
a response is received, the service aid will then display one of the following messages:
The service aid transmitted a SCSI Inquiry Command and received a valid response back
without any errors being detected.
The service aid transmitted a SCSI Inquiry Command and did not receive any response
or error status back.
The service aid transmitted a SCSI Inquiry Command and the adapter indicated a SCSI
bus error.
The service aid transmitted a SCSI Inquiry Command and an adapter error occurred.
The service aid transmitted a SCSI Inquiry Command and a check condition occur.
When the SCSI Bus Service Aid is entered a description of the service aid is displayed.
Pressing the Enter key will display the Adapter Selection menu. This menu allows the user
to enter which address to transmit the SCSI Inquiry Command.
When the adapter is selected the SCSI Bus Address Selection menu is displayed. This
menu allows the user to enter which address to transmit the SCSI Inquiry Command.
Once the address is selected the SCSI Bus Test Run menu is displayed. This menus allows
the user to transmit the SCSI Inquiry Command by pressing the Enter key. The Service Aid
will then indicate the status of the transmission. When the transmission is completed, the
results of the transmission will be displayed.
Notes:
1. A Check Condition can be returned when there is nothing wrong with the bus or
2. AIX will not allow the command to be sent if the device is in use by another
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Operator Guide
device.
process.