AMCC 9500S User Manual

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Chapter 2. CLI Syntax Reference
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3ware Serial ATA RAID Controller CLI Guide 
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. Th
is 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, specifying noqpolicy has no 
effect and the default remains. If the spare unit becomes a true unit, it would 
adopt the qpolicy of the “new” unit. For JBOD, the qpolicy cannot be set 
during unit creation, and specifying noqpolicy returns an error. 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 follo
wing 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.
 For the 7/8000 
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 
 R-5 
R-6
 R-10 
 R-50 
Single 
JBOD 
Spare 
7K/8K 
No 
 No 
No
N/A
No
No
No
No   
No    
9000
a
a. Models 9500S, 9550SX, and 9590SE
No
 Yes 
Yes 
N/A
Yes 
Yes
No
No
No
9650SE
No
Yes
Yes
Yes
Yes
Yes
No
No
No