ADSM-L

Re: Trouble with Optical Media 4GB or larger ...FLASH

2002-11-21 17:43:27
Subject: Re: Trouble with Optical Media 4GB or larger ...FLASH
From: TAZ <switchback60 AT HOTMAIL DOT COM>
To: ADSM-L AT VM.MARIST DOT EDU
Date: Thu, 21 Nov 2002 15:54:05 -0700
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Attention:
Customers running Tivoli Storage Manager (TSM) 5.1 using a TSM Server on
Windows NT or Windows 2000 and writing to optical platters that have a
capacity greater than 4Gb (4294967295 bytes) per side will not be able to
retrieve data.  This includes 5.25", dual sided 9.1 GB optical media
written using HP 9100mx and Sony SMO-F561 optical drives.  If you are not
using 9.1 GB optical media on Windows 2000 or NT server platform, you are
not affected by this problem.


Immediate Action Needed:

Customers should immediately stop storing data to 9.1GB optical media.  To
do so,  use the QUERY VOLUME command specifying the STATUS=FILLING option to
list volumes that are filling.   For each 9.1GB volume listed, use the
UPDATE VOLUME command specifying the ACCESS=READONLY option.  This will
allow any data currently on the media to be accessed while preventing any
further writes to the volume.  For 9.1GB optical volumes that are not
assigned to a storage pool and are available for scratch selection, they
should be removed from the library using the CHECKOUT LIBVOLUME command.
This will prevent these volumes from being written to.

Depending on which type of optical media is being used, WORM or re-writable
(R/W) 9.1GB optical media, the symptoms of the problem may differ.  Refer
to the appropriate section below for a description of the problem for your
particular media.


9.1GB WORM Optical Media Problem Description:

Customers running TSM 5.1 and above utilizing 9.1GB optical WORM media on
Windows operating systems will be affected by apar IC34980.  TSM server
development has identified a problem in this environment when the media is
filled to or beyond 4GB's on each side.  As a result, data written by TSM
beyond 4GB per side will not be readable.

When TSM writes data to 9.1GB WORM media,  the following error is seen when
attempting to write past 4 GB on the first side of the platter:

ANR8302E I/O error on drive OPTDRIVE2 (opX.X.X.X)
(OP=TEST_READY, Error Number=1117, CC=415, KEY=08, ASC=92,
ASCQ=00,SENSE=F1.00.08.00.10.06.4C.0E.00.00.00.00.92.00.00.00.00.00.02.50.00
.00.,
Description=Attempted to overwrite written WORM media).  Refer to Appendix
D in the 'Messages' manual for recommended action.

Following the error described above, TSM will update the volume's access to
READ-ONLY to prevent attempts to further write to the volume.


9.1GB Re-writable Optical Media Problem Description:

Customers running TSM 5.1 and above utilizing 9.1GB optical Re-writable
media on Windows operating systems will be affected by apar IC34980.  TSM
server development has identified a problem in this environment when the
media is filled to or beyond 4GB's on each side.  As a result, data written
by TSM beyond 4GB per side will not be readable.

When TSM writes data to 9.1GB R/W media, no errors are encountered until
the media is filled beyond 4GB's per side.  Once this occurs, the position
of the next write is unchanged from it's current location.  Subsequently,
any additional attempts to write data on the media beyond 4GB's occurs on
the same location of the media.  TSM is unable to determine this error is
occurring and goes on until the media is filled on both sides.  This
results in approximately 400M worth of data on each side (800MB total) that
may be lost.


Problem Resolution:

APAR IC34980 will enable TSM to write and read data correctly beyond 4GB's
per side without error.  All 9.1GB optical media written by TSM must have
it's data moved to other media within the storage pool.  Apply the ptf once
it is made available and perform the following these steps:

For each 9.1GB volume affected by this error:
   Audit the volume using the AUDIT VOLUME FIX=NO command.  This will mark
any unreadable files as damaged and display the name of the damaged
   file.   Perform a MOVE DATA command to move any undamaged files to other
media  within the storage pool.
   If backup copies were made from a storage pool other than the one
   containing the damaged optical media, perform the RESTORE VOLUME command
to recover the damaged files.

   If no backup copies were made, backup or archive the files again into
   the TSM storage hierarchy via the TSM Backup/Archive client or TSM
   Client API using the appropriate application.    At this point, if there
are files that could not be moved, perform the   DELETE VOLUME DISCARD=YES
command to remove any references to the  damaged files.  Re-writable media
can now be reused as scratch while WORM media should be removed from the
library and physically discarded.

The upcoming releases that contain the fix will be 5.1.5.3   and 5.1.6.
This will be available shortly.

I would like to thank Tivoli for releasing this information ASAP upon
discovery.


   Sam J. Giallanza

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