VERITAS Volume Manager 3.5 Migration Guide (August 2002)

Glossary 71
set of continuous physical extents [PEs]
Set of physical sectors (blocks) contained within a single physical volume. A physical
extent is a specific, contiguous region of the disk where data resides. This is of a constant
size usually of 4 MB and has no partitions.
VGRA
The Volume Group Reserved Area (VGRA) is a region on an LVM disk that holds LVM
configuration information and is at a fixed location. The location of this fixed location
depends upon whether the disk is a boot disk or a non-boot disk. For boot disks, the
VGRA starts at sector 2144. For non-boot disks, the VGRA starts at sector 128.
volume group
The collective identity of a set of physical volumes, which provide disk storage for the
logical volumes. A set of physical volumes whose space can be combined and logically
divided up into logical volumes. Only logical volumes and physical volumes that are a
part of a volume group can map together, a physical volume can belong to only one
volume group.