If you have already created a physical volume, volume group, or logical volume by using LVM, you can use the procedure described in Settings for LVM2 only when all of the conditions below are satisfied. Migration is not affected even when a logical volume or file system has been created.
A physical volume is created for only one of the logical device files on any one path for each SCSI device to be managed by HDLM. In addition, a volume group is created for only the physical volume.
This subsection describes how to check whether this condition exists.
The logical volume is unmounted.
The following explains how to check whether the above condition exists when the volume group vg02 consists of either one physical volume or two physical volumes. Note that /dev/sde and /dev/sdu are assumed to be the logical device files of SCSI devices defined for the same device to be managed by HDLM.
To check the physical volumes that belong to the volume group vg02, execute the following command:
# vgdisplay -v
The following figures show examples of command execution when the volume group consists of only one physical volume (condition satisfied) and when the volume group consists of two physical volumes (condition not satisfied).
Check the shaded portion and confirm that vg02 consists of /dev/sde.
Check the shaded portion and confirm that vg02 consists of /dev/sde and /dev/sdu, both of which have been defined for the same device to be managed by HDLM.