Veritas Volume Manager 5.1 SP1 Administrator"s Guide (5900-1506, April 2011)

row is the minimal number of disks necessary to support the full width of a parity
stripe.
Figure 1-21 shows the row and column arrangement of a traditional RAID-5 array.
Figure 1-21
Traditional RAID-5 array
Row 0
Row 1
Column 0 Column 1 Column 2 Column 3
Stripe 1
Stripe3
Stripe 2
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 columns, and rows to
be of equal size.
Veritas Volume Manager RAID-5 arrays
The RAID-5 array structure in Veritas Volume Manager differs from the traditional
structure. Due to the virtual nature of its disks and other objects, VxVM does not
use rows.
Figure 1-22 shows how VxVM uses columns consisting of variable length subdisks,
where each subdisk represents a specific area of a disk.
Understanding Veritas Volume Manager
Volume layouts in VxVM
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