IT26719: BACKUP WITH CLIENT-SIDE DEDUP MAY BE CHANGED TO NON-DEDUP

8.1.7.000-IBM-SPSRV-Linuxppc64le
8.1.7.000-IBM-SPCMS-WindowsX64
8.1.7.000-IBM-SPCMS-WindowsI32
8.1.7.000-IBM-SPCMS-Linuxx86_64
8.1.7.000-IBM-SPOC-WindowsX64
8.1.7.000-IBM-SPOC-Linuxx86_64
8.1.7.000-IBM-SPOC-Linuxs390x
8.1.7.000-IBM-SPOC-LinuxPPC64le
8.1.7.000-IBM-SPOC-AIX
8.1.7.000-IBM-SPSRV-WindowsX64
8.1.7.000-IBM-SPSRV-Linuxx86_64
8.1.7.000-IBM-SPSRV-Linuxs390x
8.1.7.000-IBM-SPSRV-AIX
IBM Spectrum Protect Server V8.1 Fix Pack 7 (V8.1.7) Downloads

APAR status

• Closed as program error.

Error description

• Problem Description:
  Client-side data deduplication backup might be run with non data
  deduplication after that unsuccessful DEDUP message was logged.
  
     ANS0266I dsmEndTxn vote is ABORT, check the source field.
     ANS7899E The client referenced a deduplicated extent that
  does not exist on the IBM Spectrum Protect server
     ANS9389W The DEDUP backup attempt was unsuccessful for
  virtual machine 'vmname'. Retry #1 with DEDUP disabled.
  
  The issue can occur on non-VM backups also.
  
  IBM Tivoli Storage Manager/IBM Spectrum Protect Versions
  affected:
  IBM Spectrum Protect Server all supported versions for all
  platforms
  
  
  Additional Keywords:
  backup; dedup; TS001194103
  
  
  Customer/L2 Diagnostics (If Applicable)
  Capture the server trace with enabling SDCREATE SDDEDUP SDRTRV
  SDDEL SDCLOUD SDCLOUDDETAIL SDUTIL IMEXP IMDEL.
  
  Example:
  At beginning, refCount of chunk -1400104815834537494 was
  1881890.
  
  06:31:19.779 [79][sddedup.c][1483][sdFindChunkInPool]:This is a
  query session
  06:31:19.991 [79][sddedup.c][3211][FindChunkInDB]:Chunk
  -1400104815834537494 is a match based on refCount of 1881890
  
  During backup session, chunk -1400104815834537494 cannot be used
  as the base chunk because refcount 2139554 is higher than
  sdMaxRefCountForLinkage.
  
  Backup session:
  06:31:28.499 [101][sddedup.c][3145][FindChunkInDB]:Evaluating
  chunk -7818607152539614344 for SHA1 C457CAC9
  06:31:28.499 [101][sddedup.c][3159][FindChunkInDB]:Chunk
  -7818607152539614344 is not a match based on maximum number of
  references encountered 2011798
  .................................
  06:31:28.708 [101][sddedup.c][3159][FindChunkInDB]:Chunk
  -1400104815834537494 is not a match based on maximum number of
  references encountered 2139554
  06:31:28.709 [101][sddedup.c][3317][FindChunkInDB]:Exit:
  rc=1116, no match found - poolId 8, chunkSize 50002, SHA1
  C457CAC9, chunkId 0, flags 0, compressed True.
  
  Between time 06:31:19.991 and 06:31:28.708, chunk
  -1400104815834537494 refcount increased and reached max refcount
  number.
  So there is a timing window between query session and real
  backup session.
  
  
  Initial Impact:
  middle
  

Local fix

• Setting the option "sdMaxRefCountForLinkage" decreases the
  possibility happening the issue, but it does not resolve it
  completely.
  The default value is 2000000.
  
  setopt sdMaxRefCountForLinkage 3000000
  

Problem summary

• ****************************************************************
  * USERS AFFECTED:                                              *
  * All IBM Spectrum Protect server users.                       *
  ****************************************************************
  * PROBLEM DESCRIPTION:                                         *
  * See error description.                                       *
  ****************************************************************
  * RECOMMENDATION:                                              *
  * Apply fixing level when available. This problem is currently *
  * projected to be fixed                                        *
  * in level 8.1.7.  Note that this is subject to change at the  *
  * discretion of IBM.                                           *
  ****************************************************************
  

Problem conclusion

• This problem was fixed.
  Affected platforms for reported release:  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