Make sure that you have HP/UX patch PHKL_18271 (or a later superceding
patch) on.  Also, if you have your DLT drives attached to an HP-PB bus, make
sure the firmware level of the SCSI adapter card is 3728 or above.  If these
are on HP-PB and you have HSC SCSI adapters available, I would advise you
move to HSC for reasons of performance and reduced I/O error type problems.
Also make sure you DLT drive microcode levels are the most current.

Thanks,
Bernie Survoy
MVS Systems Engineer
216.615.9324 phone
216.621.5920 fax
StorageTek
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