Veritas Volume Manager 5.0.1 Administrator's Guide, HP-UX 11i v3, First Edition, November 2009

Note: You need a full license to use this feature.
You can create RAID-5 volumes by using either the vxassist command
(recommended) or the vxmake command. Both approaches are described below.
A RAID-5 volume contains a RAID-5 data plex that consists of three or more
subdisks located on three or more physical disks. Only one RAID-5 data plex can
exist per volume. A RAID-5 volume can also contain one or more RAID-5 log plexes,
which are used to log information about data and parity being written to the
volume.
See “RAID-5 (striping with parity)” on page 47.
Warning: Do not create a RAID-5 volume with more than 8 columns because the
volume will be unrecoverable in the event of the failure of more than one disk.
To create a RAID-5 volume, use the following command:
# vxassist [-b] [-g diskgroup] make volume length layout=raid5 \
[ncol=number_of_columns] [stripewidth=size] [nlog=number] \
[loglen=log_length]
Specify the -b option if you want to make the volume immediately available for
use.
See “Initializing and starting a volume” on page 303.
For example, to create the RAID-5 volume volraid together with 2 RAID-5 logs
in the disk group, mydg, use the following command:
# vxassist -b -g mydg make volraid 10g layout=raid5 nlog=2
This creates a RAID-5 volume with the default stripe unit size on the default
number of disks. It also creates two RAID-5 logs rather than the default of one
log.
If you require RAID-5 logs, you must use the logdisk attribute to specify the disks
to be used for the log plexes.
RAID-5 logs can be concatenated or striped plexes, and each RAID-5 log associated
with a RAID-5 volume has a complete copy of the logging information for the
volume. To support concurrent access to the RAID-5 array, the log should be
several times the stripe size of the RAID-5 plex.
It is suggested that you configure a minimum of two RAID-5 log plexes for each
RAID-5 volume. These log plexes should be located on different disks. Having two
Creating volumes
Creating a RAID-5 volume
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