Convert volume group metadata format
vgconvert [--commandprofile ProfileName] [-d|--debug] [-h|--help] [-t|--test] [-v|--verbose] [--labelsector] [--bootloaderareasize size] [-M|--metadatatype type] [--pvmetadatacopies NumberOfCopies] [--metadatasize size] [--version] VolumeGroupName [VolumeGroupName...]
vgconvert converts VolumeGroupName metadata from one format to another provided that the metadata fits into the same space.
See lvm(8) and pvcreate(8) for options.
Convert volume group vg1 from LVM1 metadata format to the new LVM2 metadata format.
vgconvert -M2 vg1
Use pvscan(8) to see which PVs lost their metadata. Run pvcreate(8) with the --uuid and --restorefile options on each such PV to reformat it as it was, using the archive file that vgconvert(8) created at the start of the procedure. Finally run vgcfgrestore(8) with that archive file to restore the original metadata.