Digital Equipment RW504-ZA, Руководство по обслуживанию

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4.8 Error Information Through SCSI Commands
When there are errors in autochanger movements, two main approaches are
available to get information and to run execiser tests. The approach usually
depends on whether the error encountered was a hard error or whether it was a
soft or intermittent error.
• Troubleshooting Using the Control Panel and Observation - This method is
usually used in situations where you have a hard error.
• Troubleshooting Through the SCSI Bus - This method is used in situations
where you have a soft or intermittent error.
Using data on the SCSI bus, you can determine exactly what the autochanger
was doing when a failure occurred; all the way down to the macro-move and
micro-moves.
Also, through the Log Sense and Request Sense commands, you can gather
information on the optical drives; which cannot be done through the control
panel.
See Appendix A for information on decoding VMS operating system error logs and
SCSI-2 codes.
An external utility is needed to read the data on the SCSI bus. Hewlett-Packard
offers a diagnostic utility called DOSDASS2 that provides this capability. This
utility is not offered to the field, however, it is available from Hewlett-Packard or
Digital CSC (refer to Appendix B for ordering information).
4–30 Troubleshooting and Diagnostics