IJ11841: LVM CONFIG CHANGES WHILE DISKS ARE MISSING CAN CAUSE PROBLEMS APPLIES TO AIX 7100-05

APAR status

• Closed as program error.

Error description

• If certain LVM config changes are made while a disk
  in the VG is missing, when the disks are made available
  again, parts of the metadata may remain outdated.
  
  This can cause later LVM commands to fail.
  
  We have seen this when for example:
  # chvg -r y <vgname>
  is used for the first time on a VG while a disk is
  missing.
  A subsequent varyoffvg / varyonvg may fail due to
  misinterpretation of metadata.
  

Local fix

• If this is caught before the VG is varied off, the disk
  can
  be brought back active and the config command re-run, to
  correctly update metadata on that disk and avoid issues.
  

Problem summary

• If disks are missing or removed when certain LVM config changes
  are done (ones that require incrementing the VG version)...
  Later on when those disks are made active again, they may not
  get one particular bit of metadata called the 'lvmrec' updated
  with the new version number.  This could result in a later
  'varyonvg' failing, depending on the ordering of the disks,
  especially if the last disk in the VG is the one that was
  missing.
  

Problem conclusion

• Add logic in chpv -va and varyonvg to update the lvmrec version
  on disks that have an older version.
  

Temporary fix

Comments

• 7100-04 - use AIX APAR IJ13635
  7100-05 - use AIX APAR IJ11841
  7200-01 - use AIX APAR IJ10454
  7200-02 - use AIX APAR IJ13427
  7200-03 - use AIX APAR IJ12336
  

APAR Information

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

  IJ10454

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

Fix information

• Fixed component name

  AIX5.2 WPAR F/A

• Fixed component ID

  5765H3800

Applicable component levels