Veritas Volume Manager 4.1 Administrator's Guide (HP-UX 11i v3, February 2007)

Chapter 4, Creating and Administering Disk Groups
Upgrading a Disk Group
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Upgrading a Disk Group
Note On some platforms, the first release of VERITAS Volume Manager was 3.0 or 3.2.
Prior to the release of VERITAS Volume Manager 3.0, the disk group version was
automatically upgraded (if needed) when the disk group was imported.
From release 3.0 of VERITAS Volume Manager, the two operations of importing a disk
group and upgrading its version are separate. You can import a disk group from a
previous version and use it without upgrading it.
When you want to use new features, the disk group can be upgraded. The upgrade is an
explicit operation. Once the upgrade occurs, the disk group becomes incompatible with
earlier releases of VxVM that do not support the new version.
Before the imported disk group is upgraded, no changes are made to the disk group to
prevent its use on the release from which it was imported until you explicitly upgrade it to
the current release.
Until completion of the upgrade, the disk group can be used “as is” provided there is no
attempt to use the features of the current version. Attempts to use a feature of the current
version that is not a feature of the version from which the disk group was imported results
in an error message similar to this:
VxVM vxedit ERROR V-5-1-2829 Disk group version doesn’t support
feature
To use any of the new features, you must run the vxdg upgrade command to explicitly
upgrade the disk group to a version that supports those features.
All disk groups have a version number associated with them. VERITAS Volume Manager
releases support a specific set of disk group versions. VxVM can import and perform
operations on a disk group of that version. The operations are limited by what features
and operations the disk group version supports.