In my case it was an HP compressing SCSI DAT drive.  HPRC said it was in the code (vstore) not in the hardware and rebooting was the only solution.

----------
From:   [log in to unmask]
Sent:   Monday, February 17, 1997 2:13 PM
To:     [log in to unmask]
Subject:        Re: vstore hang


   I had the same thing happen to me last week.  I also tried to down
the device, and cycled power on it, but no luck.  I called the Response
Center to see if they could use debug (or whatever) to abort the process
or release the device, or to determine the cause of the problem.  I got
the same response... reboot the system to clear the problem.  I believe
the problem started when VSTORE couldn't read the tape directory since
no files were verified.  Since I was using an IEM 8mm tape drive, the
HPRC told me it was probably a hardware problem so they wouldn't help
any further.  (Kinda understandable, but the device does look like a DAT
to the system, even using the normal DAT drivers.)

                        David N. Lukenbill

--------------------------------------------------------------------
David N. Lukenbill
Hughes Missile Systems Company, Louisville
[log in to unmask]


----------
From:       HP3000-L
Sent:       Monday, February 17, 1997 10:26 AM
To:         HP3000-L
Cc:         wgrefe
Subject:    vstore hang

Vstore has hung and is now using all available cpu time.  Abort job,
Abortio and loading another tape fail to remove the job.  I lowered its
priority so at least the d queue gets some time.  The response center
said this is a known problem and needs a reboot to fix.  Is there any
other options?  Can this be fixed or is it an undocumented feature ;-(. 
Below is the vstore job listing:

Any ideas?

 :VSTORE *T;@[log in to unmask]@;LOCAL;DIRECTORY;NODECOMPRESS

 STORE/RESTORE/VSTORE VERSION   C.50.12 (C) 1986 HEWLETT-PACKARD CO.
 SAT, FEB 15, 1997,  4:33 AM



 VSTORE ENCOUNTERED MEDIA READ ERROR ON LDEV 8  (S/R 1251)
 VSTORE ENCOUNTERED ERROR READING MEDIA DIRECTORY ON LDEV 8.
  (S/R 1281)