Avago Technologies 3ware SAS 9750-16i4e User Manual
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Unit Object Commands
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settings. The following description about the settings can help you to decide
which one is suitable to your application. For more information, refer to the
discussion of this setting in the 3ware SATA+SAS RAID Controller Card
Software User Guide, Version 10.2, under “About StorSave Profile Levels”.
protect provides the maximum data protection among the controller settings.
When storsave is set to protect mode, it means the following:
•
When the unit becomes degraded, the write cache is disabled.
•
Write journaling is enabled. All data flushing from controller cache is
flushed to media.
•
Incoming Force Unit Access (FUA) host requests are honored unless a
BBU is installed and enabled, in which case they are ignored.
perform provides the maximum performance and least data protection of the
three controller settings. When storsave is set to perform mode, it means the
following:
•
When the unit becomes degraded, the write cache is not disabled.
•
Write journaling is disabled. All data flushing from controller cache is
flushed to disk. If a BBU is present, specifying perform as the storsave
setting essentially disables the BBU for this unit.
•
Incoming FUA host requests are honored.
If you set the storsave policy to perform, a confirmation message warns you
that there could be data loss in the event of a power failure.
balance provides more data protection than perform mode but less data
protection than protect mode, and provides better performance than protect
mode but lower performance than perform mode. When storsave is set to the
balance mode, it means the following:
•
When the unit becomes degraded, the write cache is not disabled.
•
Write journaling is disabled if no BBU is present, and is enabled if a BBU
is present. All data flushing from controller cache is flushed to media if a
BBU is installed and enabled. Otherwise, data is flushed to disk only.
•
Incoming FUA host requests are honored unless a BBU is installed and
enabled, in which case, they are ignored.
quiet is used for noninteractive mode. Confirmation statements are
suppressed and the command is executed immediately. Using quiet is useful
for scripting purposes.
For additional information, see “Setting the StorSave Profile for a Unit” in the
3ware SATA+SAS RAID Controller Card Software User Guide, Version 10.2.
Example:
//localhost> /c0/u5 set storsave=protect
Setting Command Storsave Policy for unit /c0/u5 to [protect] ...
Done.