Each physical volume used by AIX LVM has a unique physical volume ID, or PVID for short. The PVID is a software-generated ID that is stored in the header area of a disk (block 0). When a new disk is added to an AIX system, the new physical volume does not yet have a PVID. As soon as a physical volume is added to a volume group, a PVID is automatically generated if the physical volume should not already have a PVID. An already existing PVID is adopted.
A PVID can also be created manually, using the chdev command. The pv attribute is set to the value yes:
# chdev -l hdisk3 -a pv=yes hdisk3 changed #
The set PVID can be displayed either with the lsattr command or simply with lspv:
$ lsattr -El hdisk3 -a pvid -F value 00c276b0084049750000000000000000 $ $ lspv |grep hdisk3 hdisk3 00c276b008404975 None $
A PVID can also be removed again. However, the physical volume must not be in use for this (e.g. as part of a volume group).
To clear a PVID of a physical volume, the pv attribute can be set to the value clear:
# chdev -l hdisk3 -a pv=clear hdisk3 changed #
The PVID has been removed as shown by the following outputs:
$ lsattr -El hdisk3 -a pvid -F value none $ $ lspv |grep hdisk3 hdisk3 none None $
Attempting to delete the PVID of a physical volume that is in use, results in the following error message:
# chdev -l hdisk0 -a pv=clear Method error (/usr/lib/methods/chgdisk): 0514-062 Cannot perform the requested function because the specified device is busy. pv #