VERITAS Volume Manager 3.1 Administrator's Guide

Introduction to Volume Manager
Volumes and Virtual Objects
Chapter 134
Figure 1-4 Example Plex With Two Subdisks
You can organize data on the subdisks to form a plex by using these
methods:
• concatenation
• striping (RAID-0)
• striping with parity (RAID-5)
• mirroring (RAID-1)
Concatenation, striping (RAID-0), RAID-5, and mirroring (RAID-1) are
described in “Virtual Object Data Organization (Volume Layouts)”.
NOTE You may need an additional license to use this feature.
Volumes
A volume is a virtual disk device that appears to applications,
databases, and file systems like a physical disk device, but does not have
the physical limitations of a physical disk device. A volume consists of
one or more plexes, each holding a copy of the selected data in the
volume. Due to its virtual nature, a volume is not restricted to a
particular disk or a specific area of a disk. The configuration of a volume
can be changed by using the Volume Manager user interfaces.
Configuration changes can be done without causing disruption to
applications or file systems that are using the volume. For example, a
volume can be mirrored on separate disks or moved to use different disk
storage.
The Volume Manager uses the default naming conventions of vol ## for
volumes and vol ##-## for plexes in a volume. Administrators must
disk01
vol01-01
disk01-01
disk01-02
vol01
disk01-01
disk01-02
Plex
Subdisks