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IT00880: EXCESSIVE SNAPLOCK VOLUMES BECOME READONLY DURING MIGRATION

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You can track all active APARs for this component.

APAR status

  • Closed as program error.

Error description

  • During migration to a snaplock  sequential storage, the
    migration process may fail with excessive snaplock volumes maybe
    set to READONLY after receiving the ANR8503E errors.
    .
    
    L2/Customer Diagnostics:
    .
    A PVR MMS AS SS AF trace shows an errno = 30 was received during
     retry  write:
    
    -Initial Write:
    20:50:35.359 [348084][pvr.c][13806][AgentThread]:PVR I/O agent
    (348084) processing WRITENC request.
    20:50:35.360 [348084][pvrfil64.c][2190][FileWriteNC]:Writing
    (48,262096) bytes to FILE volume /njssam6yv49/000CF729.BFS:
    LastOp = 3, bufBlock = -2, nextBlock = 364, offset = 48.
    ...
    20:50:38.520 [348084][pvrfil64.c][2190][FileWriteNC]:Writing
    (48,246768) bytes to FILE volume /njssam6yv49/000CF729.BFS:
    LastOp = 2, bufBlock = 373, nextBlock = 374, offset = 48
    
    .
    -Retried write failed:
    
    20:50:38.814 [348084][pvr.c][14246][AgentThread]:PVR I/O agent
    (348084) finished SEEKAPPENDPOS request; rc=0.
    20:50:38.814 [348084][pvr.c][13759][AgentThread]:PVR I/O agent
    (348084) waiting for next request.
    20:50:38.823 [348084][pvr.c][13806][AgentThread]:PVR I/O agent
    (348084) processing WRITENC request.
    20:50:38.825 [348084][pvrfil64.c][2190][FileWriteNC]:Writing
    (48,262096) bytes to FILE volume /njssam6yv49/000CF729.BFS:
    LastOp = 3, bufBlock = -2, nextBlock = 364, offset = 48.
    
    20:50:38.825 [348084][pvrfil64.c][1778][FileWrite]:Writing
    262144 bytes to FILE volume /njssam6yv49/000CF729.BFS.
    
    20:50:38.830 [348084][pspvrfio.c][539][PvrFioWrite]:Write error
    with handle 62 with errno = 30.
    
    .
    
    
    With this issue, the  activities involved after a
    write to a snaplock volume receives an error:
    
    1) During migration, a write to SnapLock volume A hits a write
    error at the operating system level
    (such as AIX errno 30).
    2) The server mounts volume B to retry the failed write.
    3) with the issue,  the server to treat the subsequent
    successful  write to volume B as having hit a write error.
    
    4) In this error path, volume B is treated as a normal volume
    rather than a SnapLock volume, so the
    successful write to volume B is attempted again.
    5) The filer correctly does not allow this write, which fails
    with errno 30.
    6) The server instructs the filer to lock volume B as read-only,
    and mounts volume C to retry the
    failed write.
    7) The bug we identified causes the server to treat the
    subsequent successful write to volume C as
    having hit a write error.
    8) We retry the successful write to volume C.
    9) The filer correctly does not allow this write, which fails
    with errno 30.
    10) The server instructs the filer to lock volume C as
    read-only.
    11) The server records the migration as having failed to migrate
    the current file.
    
    
    So a write error to snaplock volume during migration can cause
    additional two good volumes to be set to READONLY and the
    process will fail.
    
    The proper actions should be after the fix is like this:
    
    1) During migration, a write to SnapLock volume A hits a write
    error at the operating system level
    (such as AIX errno 30).
    2) The server instructs the filer to lock volume A as read-only,
    and mounts volume B to retry the
    failed write.
    3) The server successfully completes the same write to volume B
    and migration processing continues.
    
    
    
    
    Platform /Version affected
    .
    Tivoli Storage manager Server v62, V63 V71
    .
    
    Additional keywords:
    snaplock ANR8503E READONLY migration
    

Local fix

Problem summary

  • ****************************************************************
    * USERS AFFECTED:                                              *
    * All Tivoli Storage Manager server users of WORM volumes.     *
    ****************************************************************
    * PROBLEM DESCRIPTION:                                         *
    * See error description.                                       *
    ****************************************************************
    * RECOMMENDATION:                                              *
    * Apply fixing level when available. This                      *
    * problem is currently projected to be fixed                   *
    * in levels 6.3.5 and 7.1.1. Note that this is                 *
    * subject to change at the discretion of IBM.                  *
    ****************************************************************
    WORM volumes other than SnapLock, will have 512KB unusable space
    after a write error.
    

Problem conclusion

  • This problem was fixed.
    Affected platforms:  AIX, HP-UX, Solaris, Linux, and Windows.
    

Temporary fix

Comments

APAR Information

  • APAR number

    IT00880

  • Reported component name

    TSM SERVER

  • Reported component ID

    5698ISMSV

  • Reported release

    63A

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt

  • Submitted date

    2014-04-09

  • Closed date

    2014-04-17

  • Last modified date

    2014-04-17

  • 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

  • R62A PSY

       UP

  • R62H PSY

       UP

  • R62L PSY

       UP

  • R62S PSY

       UP

  • R62W PSY

       UP

  • R63A PSY

       UP

  • R63H PSY

       UP

  • R63L PSY

       UP

  • R63S PSY

       UP

  • R63W PSY

       UP

  • R71A PSY

       UP

  • R71H PSY

       UP

  • R71L PSY

       UP

  • R71S PSY

       UP

  • R71W PSY

       UP



Document information

More support for: Tivoli Storage Manager

Software version: 63A

Reference #: IT00880

Modified date: 17 April 2014