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High Impact / Highly Pervasive APAR IJ46487 potential undetected data loss after running chvg -ky or chvg -g


Risk classification

HIPER (High Impact and/or Pervasive)

Risk categories

Data Loss


IJ46487 - potential undetected data loss after running chvg -ky or chvg -g


Potential undetected data loss can occur on disks larger than 2 TB if 'chvg -ky' is run to make the VG encryption capable, or if 'chvg -g' is run on a VG that is encryption capable.

On AIX 7.3, VGs are created as encryption capable by default.  For encryption capable VGs, 'lsvg <vgname>' shows:

 ENCRYPTION:         yes

 If the 'chvg' commands above are run, a variable size block of LVM metadata can overwrite user data on disks in the VG that are larger than 2 TB.  This can occur during the chvg command execution, and also could reoccur later if the metadata is updated on disk.

Date first published

24 April 2023

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Document Information

Modified date:
24 April 2023