VERITAS Volume Manager 4.1 Administrator's Guide

Understanding VERITAS Volume Manager
Volume Layouts in VxVM
Chapter 1 31
all of the disks in the array, reducing the write time for large
independent writes because the writes do not have to wait until a single
parity disk can accept the data.
Figure 1-21 Parity Locations in a RAID-5 Model
RAID-5 and how it is implemented by the VxVM is described in “Volume
Manager RAID-5 Arrays” on page 32.
RAID-5 volumes can additionally perform logging to minimize recovery
time. RAID-5 volumes use RAID-5 logs to keep a copy of the data and
parity currently being written. RAID-5 logging is optional and can be
created along with RAID-5 volumes or added later.
Traditional RAID-5 Arrays
A traditional RAID-5 array is several disks organized in rows and
columns. A column is a number of disks located in the same ordinal
position in the array. A row is the minimal number of disks necessary to
Parity
Parity
Data
Data
Data
Data
Data
Parity
Data
Data
Parity
Data
Stripe 1
Stripe 4
Stripe 3
Stripe 2