>I have a Syquest EZ-135 drive, which once in a great while appears to
>return UNIT ATTENTION for no obvious reason.
>
>messages.5:Sep 18 15:40:01 jfwhome /netbsd: sd4(aha0:4:0): unit attention, dat
>a = 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>
>If it is mounted at the time, this renders the drive unusable until I
>reboot.

Can you find out what the ASC and ASQ are for that sense operation?
I think that you will get more specific information about what caused
the UNIT ATTENTION by looking at them and that the code in scsi_base.c
should be more restrictive in what causes it to believe it should
invalidate the media.

--
Justin T. Gibbs
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  FreeBSD: Turning PCs into workstations
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