VERITAS Volume Manager 3.5 Administrator's Guide (September 2004)
Creating Volumes
Creating a Mirrored Volume
Chapter 7228
Creating a Mirrored Volume
A mirrored volume provides data redundancy by containing more than
one copy of its data. Each copy (or mirror) is stored on different disks
from the original copy of the volume and from other mirrors. Mirroring a
volume ensures that its data is not lost if a disk in one of its component
mirrors fails.
NOTE A mirrored volume requires space to be available on at least as many
disks in the disk group as the number of mirrors in the volume.
To create a new mirrored volume, use the following command:
# vxassist [-b] [-g diskgroup] make volume length
layout=mirror [nmirror=number] [init=active]
NOTE Specify the -b option if you want to make the volume immediately
available for use. See “Initializing and Starting a Volume” on page 244
for details.
For example, to create the mirrored volume, volmir, use the following
command:
# vxassist -b make volmir 5g layout=mirror
To create a volume with 3 instead of the default of 2 mirrors, modify the
command to read:
# vxassist -b make volmir 5g layout=mirror nmirror=3
Creating a Mirrored-Concatenated Volume
A mirrored-concatenated volume mirrors several concatenated plexes. To
create a concatenated-mirror volume, use the following command:
# vxassist [-b] [-g diskgroup] make volume length
layout=mirror-concat [nmirror=number]