Veritas Volume Manager 5.0.1 Migration Guide, HP-UX 11i v3, First Edition, November 2009

Note: Restoring user data using the vgrestore and frecover method will result
in the loss of all user data changes made since the conversion, and the loss of all
new volumes created since the conversion.
In other words, this method of restoring data will take you back to exactly where
you were before the conversion was done.
However, if no new volumes have been created, and if none of the existing volumes
have been resized, you can use the vxvmconvert rollback option to restore the
original LVM configuration. If you use this method, any user data changes made
since the conversion will be retained, and you will not need to carry out a user
level data restore (frecover).
The name changes that vxvmconvert makes as part of the conversion are managed
by rollback, and do not count as VxVM configuration changes for the purposes of
choosing a restoration method.
The vgrestore command should not be confused with the LVM command,
vgcfgrestore. vgcfgrestore is used to restore the LVM configuration information
saved by vgcfgbackup, but it will not restore your device files and/etc/fstab
entries. It also will not import and activate the volume group, nor will it clean up
any VxVM information left around. However, vgrestore will do all of this for you.
Rollback to LVM using vxvmconvert
Rollback replaces the VxVM disk groups with the original LVM volume groups.
During conversion, vxvmconvert saves a “snapshot” of the original LVM metadata
and associated configuration files, such as /etc/fstab and LVM device files. It
restores only the LVM metadata and configuration files from this snapshot; user
data is not changed. This method can only be used if no changes have been made
to the configuration since the conversion.
For example, if a disk has been added to the disk group or if the names of any
logical volumes have changed, you cannot use the rollback method.
35Converting LVM to VxVM
Restoring the LVM volume group configuration