VERITAS Volume Manager 3.1 Administrator's Guide

Introduction to Volume Manager
Volume Manager and RAID-5
Chapter 1 49
Figure 1-15 Traditional RAID-5 Array
This traditional array structure supports growth by adding more rows
per column. Striping is accomplished by applying the first stripe across
the disks in Row 0, then the second stripe across the disks in Row 1, then
the third stripe across the Row 0 disks, and so on. This type of array
requires all disks (partitions), columns, and rows to be of equal size.
Volume Manager RAID-5 Arrays
The Volume Manager RAID-5 array structure differs from the traditional
structure. Due to the virtual nature of its disks and other objects, the
Volume Manager does not use rows. Instead, the Volume Manager uses
columns consisting of variable length subdisks, as shown in Figure 1-16,
Volume Manager RAID-5 Array,. Each subdisk represents a specific area
of a disk.
Column 0 Column 1 Column 2 Column 3
Row 0
Row 1
Stripe 1
Stripe 3
Stripe 2