HP StorageWorks HSG60 and HSG80 Array Controller and Array Controller Software Command Line Interface Reference Guide (EK-G80CL-RA. C01, March 2005)

CLI Command Descriptions
224 HP StorageWorks HSG60 and HSG80 Array Controller and Array Controller Software
Command Line Interface Reference Guide
Switches
The following switch supports the SET NOFAILOVER command:
DESTROY_UNFLUSHABLE_DATA
NODESTROY_UNFLUSHABLE_DATA (default)
Instructs the controller how to handle data contained within writeback cache.
These switches have no effect if both controllers are operational. Select one of
these switches to indicate how the controller is to handle data contained in
cache if one of the controllers fails before it can properly shut down with the
SET NOFAILOVER, SET NOMULTIBUS_FAILOVER, or SHUTDOWN
controller commands.
Under some circumstances, the data in the writeback cache of a failed
controller may not fail over to the writeback cache of the operating controller.
For example, cache data does not fail over if the operating controller has a
failed cache battery because of the risk of data loss if the power is interrupted.
■ Specify NODESTROY_UNFLUSHABLE_DATA to leave the unwritten
data intact in the writeback cache of the failed controller. After the failed
controller is replaced and placed into service, the writeback cache data is
flushed to the appropriate devices.
■ Specify DESTROY_UNFLUSHABLE_DATA to reconfigure the
operational controller before replacing the failed controller. The unwritten
data of the failed controller can reference devices not present in the new
configuration. If you do not destroy the old configuration data, it can
conflict with the new configuration and cause the subsystem to behave
unpredictably.
Caution: Unflushed data cannot be recovered after it is destroyed.
Example
To terminate Transparent Failover mode between two controllers in a
dual-redundant configuration, enter:
SET NOFAILOVER