Before you can use a disk or disk partition as a physical volume you will have to initialize it:
For entire disks:
Run pvcreate on the disk:
# pvcreate /dev/hdb
If you get an error that LVM can't initialize a disk with a partition table on it, first make sure that the disk you are operating on is the correct one. If you are very sure that it is, run the following:
The following commands will destroy the partition table on the disk being operated on. Be very sure it is the correct disk.
# dd if=/dev/zero of=/dev/diskname bs=1k count=1 # blockdev --rereadpt /dev/diskname
When using LVM 1 on PCs with DOS partitions, set the partition type to 0x8e using fdisk or some other similar program. This step is unnecessary on PPC systems or when using LVM 2.
Run pvcreate on the partition:
# pvcreate /dev/hdb1