IT30966: INVALID BLOCK HEADER ERRORS GENERATED DURING TAPE READ OPERATIONS

8.1.10.000-IBM-SPOC-WindowsX64
8.1.10.000-IBM-SPOC-Linuxx86_64
8.1.10.000-IBM-SPOC-Linuxs390x
8.1.10.000-IBM-SPOC-LinuxPPC64le
8.1.10.000-IBM-SPOC-AIX
8.1.10.000-IBM-SPCMS-WindowsX64
8.1.10.000-IBM-SPCMS-WindowsI32
8.1.10.000-IBM-SPCMS-Linuxx86_64
8.1.10.000-IBM-SPSRV-WindowsX64
8.1.10.000-IBM-SPSRV-Linuxx86_64
8.1.10.000-IBM-SPSRV-Linuxs390x
8.1.10.000-IBM-SPSRV-Linuxppc64le
8.1.10.000-IBM-SPSRV-AIX
IBM Spectrum Protect Server V8.1 Fix Pack (V8.1.10) Downloads

APAR status

• Closed as program error.

Error description

• Attempted tape reads may fail due to "invalid block header"
  errors similar to the following:
  
  ANR9999D_1464158388 ComBlockHeaderValid(pvrgts.c:7259)
  Thread<20>: Invalid block header read from volume AA0000L7.
  (magic=C5D6C6F1, ver=3250905812, Hdr blk=1273360624 <expected
  4294967282>, db=4042322160 <262144,262144,0>)
  ANR9999D Thread<20> issued message 9999 from:
  ANR9999D Thread<20> 0x129be82
  /opt/tivoli/tsm/server/bin/dsmserv(OutDiagToCons+0xa2)
  ANR9999D Thread<20> 0x129ec2c
  /opt/tivoli/tsm/server/bin/dsmserv(outDiagfExt+0x1fc)
  ANR9999D Thread<20> 0x13bdf9f
  /opt/tivoli/tsm/server/bin/dsmserv(ComBlockHeaderValid+0x11f)
  ANR9999D Thread<20> 0x13be2f2
  /opt/tivoli/tsm/server/bin/dsmserv(ValidateBlockHdr+0xa2)
  ANR9999D Thread<20> 0x13c5aed
  /opt/tivoli/tsm/server/bin/dsmserv(PvrGtsRead+0x47d)
  ANR9999D Thread<20> 0xc1a7f5
  /opt/tivoli/tsm/server/bin/dsmserv(AgentThread+0x335)
  ANR9999D Thread<20> 0x136d440
  /opt/tivoli/tsm/server/bin/dsmserv(StartThread+0x90)
  ANR9999D Thread<20> 0x7f2c5c7aa724
  /lib64/libpthread.so.0(+0x8724)
  ANR9999D Thread<20> 0x7f2c57f29e8d /lib64/libc.so.6(clone+0x6d)
  
  Despite these errors, there are no problems with the block
  header and the data on the tape is valid; the problem is with
  the read request.  Beginning in the 8.1.8.0 version of Spectrum
  Protect server code, the SILI bit is enabled for SCSI read
  operations by the IBM Spectrum Protect device driver.  With the
  SILI bit enabled, the tape drive firmware will return the
  requested data length for the block being read, whereas when the
  SILI bit is disabled the tape drive will return the actual data
  length.  The following trace excerpt shows the expected behavior
  when the SILI bit is disabled; a read of 1024 bytes is
  requested, but only 80 bytes of data was read because this is
  all of the data that was contained in the block:
  
  20:50:56.688 [20][pvrgts.c][3984][PvrGtsLocateMTOC]:Locating
  MTOC on tape volume AA0000L7.
  20:52:46.554 [20][pspvr.c][4000][PvrPsDevRead]:handle = 13, read
  amt = 80, numBytes requested = 1024, errno = 0
  20:52:46.554 [20][pvrgts.c][4040][PvrGtsLocateMTOC]:Read 80
  bytes, expecting 80 or more bytes.
  
  The following trace excerpt shows the same read operation when
  the SILI bit is enabled; although the block only contains 80
  bytes of data, 1024 bytes of data are read because this was the
  amount of data that was requested:
  
  20:39:26.324 [24][pvrgts.c][3984][PvrGtsLocateMTOC]:Locating
  MTOC on tape volume AA0000L7.
  20:41:16.197 [24][pspvr.c][4000][PvrPsDevRead]:handle = 15, read
  amt = 1024, numBytes requested = 1024, errno = 0
  20:41:16.197 [24][pvrgts.c][4040][PvrGtsLocateMTOC]:Read 1024
  bytes, expecting 80 or more bytes.
  
  The "invalid block header" errors are only seen when the
  requested data length does not match the actual data length for
  the block being read.
  
  | MDVREGR 8.1.8-5698ISMSV |
  
  Spectrum Protect Versions Affected:
  Server versions 8.1.8.0 and higher on AIX, Linux and Windows
  
  Initial Impact:
  Medium
  
  Additional Keywords:
  SILI TS002924817
  

Local fix

• The problem can be circumvented on Windows and AIX platforms by
  installing the 8.1.7 (or prior) version of the IBM Spectrum
  Protect device driver.  There is no circumvention for Spectrum
  Protect servers running on Linux.
  

Problem summary

• ****************************************************************
  * USERS AFFECTED:                                              *
  * All IBM Spectrum Protect server users of DB RESTORE with all *
  * tape devices.                                                *
  ****************************************************************
  * PROBLEM DESCRIPTION:                                         *
  * See error description.                                       *
  ****************************************************************
  * RECOMMENDATION:                                              *
  * Apply fixing level when available.                           *
  * This problem is currently projected to be fixed in levels    *
  * 8.1.9.100 and 8.1.10.                                        *
  * Note that this is subject to change at the discretion of     *
  * IBM.                                                         *
  ****************************************************************
  

Problem conclusion

• The problem was fixed.
  Affected platforms:  AIX, Linux, and Windows.
  Platforms fixed:  AIX, Linux, and Windows.
  

Temporary fix

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

• APAR is sysrouted TO one or more of the following:

Fix information

• Fixed component name

  TSM SERVER

• Fixed component ID

  5698ISMSV

Applicable component levels

• R81A PSY

     UP

• R81L PSY

     UP

• R81W PSY

     UP