ANR9999D message - Vol History Deadlock

Date:     January 13, 1997            Time:    17:59
From:    Jerry Lawson
    ITT Hartford Insurance Group
    (860) 547-2960    jlawson AT itthartford DOT com
-----------------------------------------------------------------------------
We have been encountering problems with tapes not being returned to scratch
We have been encountering problems with tapes not being returned to scratch
status after they have been emptied.  They seem to be used in reclaimations,
and then I receive the following messages.


  01/11/1997 00:26:44    ANR9999D ICUTIL(718): Lock acquisition (ixLock)
failed for IC universe.
  01/11/1997 00:26:44    ANR9999D ICVOLHST(1986): Lock Conflict encountered in
updating volume history list.

The tapes then appear as "empty", and ADSM then selects them as output tapes,
but we fail when we try to mount them.  This happens repetitively, and our
storage pool migrations fail trying to mount them, and our storage pool fills
up.

Does anyone know what causes this kind of deadlock?  Other tapes seem to be
processed normally.  This does occur around midnight, so some server
activities are also underway, but we do not purge the volume history file
until noon.

*****************************************************************************
Jerry Lawson
ITT Hartford Insurance Group
jlawson AT itthartford DOT com