VERITAS Volume Manager 3.5 Migration Guide (August 2002)

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Glossary
block
A unit of space for data on a disk, typically having a size of 1024-bytes.
Dirty Region Logging
Dirty Region Logging (DRL) is an optional property of a volume, used to provide a
speedy recovery of mirrored volumes after a system failure. DRL keeps track of the
regions that have changed due to I/O writes to a mirrored volume.
file system
The organization of files on storage devices. The term file system can refer either to the
entirefile system or to asubsection of that file system,contained within a disk sectionor a
logical volume that can be mounted or unmounted from that tree.
logical volume
A logical structure that is a map of storage areas on physical volumes. A logical volume
can be conceptualized as a storage device of flexible size. The data in a logical volume can
be mapped to one or more physical volumes. A virtual disk device that represents a
contiguous virtual disk space that maps to single or multiple areas on a single or multiple
physical volumes.
LVM
The Logical Volume Manager (LVM) is a subsystem for managing disk space. LVM is an
HP-UX product, similar to VxVM.
LIF
The Logical Interchange Format (LIF) is a HP mass-storage format that can be used for
interchange of files among various HP computer systems. Each boot disk has a LIF
directory that contains boot programs.