Table of Contents
Advertisement
Chapter 2. CLI Syntax Reference
42
The default RAID 50 grouping varies, based on number of disks. For 6 and 9
disks, default grouping is 3. For 8 disks, the default grouping is 4. For 10
disks, the default grouping is 5, and for 12 disks, the disks can be grouped into
groups of 3, 4, or 6 drives (the group of 4 drives is set by default as it provides
the best of net capacity and performance). For 15 disks, the disks can be
grouped into groups of 3 or 5 drives. For 16 disks, the disks can be grouped
into groups of 4 or 8 drives.
noscan attribute instructs CLI not to notify the operating system of the
creation of the new unit. By default CLI will inform the operating system.
One application of this feature is to prevent the operating system from
creating block special devices such as /dev/sdb and /dev/sdc as some
implementations might create naming fragmentation and a moving target.
nocache attribute instructs CLI to disable the write cache on the newly
created unit. Enabling write cache increases write performance at the cost of
potential data loss in case of sudden power loss (unless a BBU or UPS is
installed). By default the cache is enabled. To avoid the possibility of data loss
in the event of a sudden power loss, it is recommended not to set nocache
unless there is a BBU (battery backup unit) or UPS (uninterruptible power
supply) installed.
autoverify attribute enables the autoverify attribute on the unit that is to be
created. For more details on this feature, see "/cx/ux set autoverify=on|off" on
page 68. This feature is not supported on model 7000/8000. On model 9000,
the JBOD autoverify attribute is not persistent (does not survive reboots).
noqpolicy attribute instructs CLI to disable the qpolicy (drive queuing) on the
newly created unit. The default is for the qpolicy to be on (in other words,
noqpolicy is not specified). For a spare unit, drive queuing is not meaningful,
so the noqpolicy cannot be set. During unit creation, specifying noqpolicy for
a spare returns an error. (If the spare unit becomes a true unit, it will adopt the
qpolicy of the "new" unit.) For more about drive queuing, see "/cx/ux show
qpolicy" on page 62 and "/cx/ux set qpolicy=on|off" on page 70.
ignoreECC attribute enables the ignoreECC/OverwriteECC attribute on the
unit that is to be created. For more details on this feature, see "/cx/ux set
ignoreECC=on|off" on page 69. The following table illustrates the supported
Model-Unit Types. This table only applies to setting this feature at unit
creation time. IgnoreECC only applies to redundant units.
series, this setting is only applicable during rebuild; it is not applicable
during creation.
Table 8: Supported Model-Unit Types for ignoreECC
Model
R-0
R-1
7K/8K
No
No
R-5
R-6
R-10
R-50
No
N/A
No
No
3ware Serial ATA RAID Controller CLI Guide
For the 7/8000
Single
JBOD
Spare
No
No
No
Advertisement
Table of Contents
