Quick Reference Guide

Mandatory Options
and Arguments
Optional Parameters Valid Parameters
Arguments
Description
• 5 — RAID 5 provides data redundancy
by using data striping in combination
with parity information. Rather than
dedicating a drive to parity, the parity
information is striped across all disks
in the array.
• 6 — RAID 6 is an extension of RAID 5
and uses an additional parity block. It
uses block-level striping with two
parity blocks distributed across all
member disks. RAID 6 provides
protection against double disk failures
and failures while a single disk is
rebuilding. In case there is only one
array, RAID 6 may be a better option
than a hot spare disk.
• 10 — RAID 10 is a stripe of mirrors.
Multiple RAID 1 mirrors are created,
and a RAID 0 stripe is created over
these.
• 50 — RAID 50 is a dual-level array
that uses multiple RAID 5 sets in a
single array. A single hard drive
failure can occur in each of the RAID
5 without any loss of data on the
entire array. Although the RAID 50 has
increased write performance, when a
hard drive fails and reconstruction
takes place, performance decreases,
data/program access is slower, and
transfer speeds on the array are
affected.
• 60 — RAID 60 is a combination of
RAID 6 and RAID 0. A RAID 0 array is
striped across RAID 6 elements. It
requires at least 8 disks.
-ctrl -ac=cvd -
c=id -ad=
ch:targ,ch:tar
g, ... [or
ch:targ:encl,.
..]
or
controller
action=
createvdisk
controllerid=
id adisk=
channel:target
: lun,
channel:target
: lun,...
[or
channel:target
:
enclosure,...]
-rp or
readpolicy
ra, ara, nra, rc, nrc
CAUTION: If the controller is changed
from SCSI to RAID mode, expect data loss
to occur. Back up any data you want to
save before changing the modes.
Sets the SCSI read policy for the virtual disk.
Specify the SCSI read policy for the logical
drive. The valid arguments are:
• ra — (read-ahead) The controller
reads sequential sectors of the disk
when seeking data.
• ara — (Adaptive Read-Ahead) The
controller initiates read-ahead only if
the two most recent read requests
accessed sequential sectors of the
disk. If subsequent read requests
access random sectors of the disk,
the controller reverts to No-Read-
Ahead policy. The controller
continues to evaluate whether or not
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