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IC71893: MOUNT_STOP SCRIPT MAY HANG IF THERE ARE MULTIPLE FS ON THE SAME VG

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You can track all active APARs for this component.

APAR status

  • Closed as program error.

Error description

  • In an integrated HA environment, if there are multiple
    filesystems exist on the same vg on AIX systems, the TSA move
    request may hang. TSA move will call the mountV9x_stop.ksh
    script on all the mount points in parallel.
    
    In the mountV9x_stop.ksh script, umount and varyoffvg commands
    are issued in a loop until varyoffvg is successful.
    
    In a scenario where there are multiple fs on the same vg, one
    mountV9x_stop.ksh script may be calling varyoffvg while the
    other mountV9x_stop.ksh may be issuing lslv prior to a umount
    attempt. Since varyoffvg is being invoked in a loop, this will
    block the lslv calls. This subsequently blocks the lslv, umount
    code path in the rest of the mountV9x_stop.ksh scripts, so those
    mount points are still mounted. This in turn causes varyoffvg
    call to fail.
    
    This race condition is sometimes seen in an environment where
    there are over 4 filesystems per vg.
    
    During this scenario, any lslv or lsvg command will hang.
    

Local fix

  • No known workaround. Please contact with the IBM db2support.
    

Problem summary

  • In an integrated HA environment, if there are multiple
    filesystems exist on the same vg on AIX systems, the TSA move
    request may hang. TSA move will call the mountV9x_stop.ksh
    script on all the mount points in parallel.
    
    In the mountV9x_stop.ksh script, umount and varyoffvg commands
    are issued in a loop until varyoffvg is successful.
    
    In a scenario where there are multiple fs on the same vg, one
    mountV9x_stop.ksh script may be calling varyoffvg while the
    other mountV9x_stop.ksh may be issuing lslv prior to a umount
    attempt. Since varyoffvg is being invoked in a loop, this will
    block the lslv calls. This subsequently blocks the lslv, umount
    code path in the rest of the mountV9x_stop.ksh scripts, so thos
    mount points are still mounted. This in turn causes varyoffvg
    call to fail.
    
    This race condition is sometimes seen in an environment where
    there are over 4 filesystems per vg.
    
    During this scenario, any lslv or lsvg command will hang.
    

Problem conclusion

  • This APAR is first fixed in the DB2 V9.7fp4
    

Temporary fix

  • No known workaround. Please contact with the IBM db2support
    

Comments

APAR Information

  • APAR number

    IC71893

  • Reported component name

    DB2 FOR LUW

  • Reported component ID

    DB2FORLUW

  • Reported release

    970

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt

  • Submitted date

    2010-10-14

  • Closed date

    2011-04-29

  • Last modified date

    2011-04-29

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

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

    IC71894 IC72005

Fix information

  • Fixed component name

    DB2 FOR LUW

  • Fixed component ID

    DB2FORLUW

Applicable component levels

  • R970 PSY

       UP



Document information

More support for: DB2 for Linux, UNIX and Windows

Software version: 9.7

Reference #: IC71893

Modified date: 29 April 2011