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
240 HP StorageWorks HSG60 and HSG80 Array Controller and Array Controller Software
Command Line Interface Reference Guide
use of this switch has the effect of setting both the
MAX_READ_CACHED_TRANSFER_SIZE and the
MAX_WRITE_CACHED_TRANSFER_SIZE switches.
PREFERRED_PATH=OTHER_CONTROLLER
PREFERRED_PATH=THIS_CONTROLLER
NOPREFERRED_PATH (default)
Allows or disallows I/O load balancing. The PREFERRED_PATH switch
allows you to balance the I/O load by specifying the controller through which
the unit is accessed. If you set NOPREFERRED_PATH for a unit, it can be
accessed through either controller.
Note: This command is only valid if in Multiple-bus Failover mode.
The controllers only use the PREFERRED_PATH setting if they are in a
dual-redundant configuration. If one controller fails, all the devices are
accessed through the remaining controller ignoring the PREFERRED_PATH
setting.
If the failed controller is restarted, the drives automatically return to the
controller specified by the PREFERRED_PATH switch.
You can specify the PREFERRED_PATH switch for a single controller
configuration; however, the switch does not take effect until you add a second
controller and configure the two controllers for dual-redundancy.
■ If no preferred path is assigned, the unit is targeted through the controller
that first detects the unit after the controllers start.
■ Select PREFERRED_PATH=THIS_CONTROLLER to instruct “this
controller” to bring the units online.
■ Select PREFERRED_PATH=OTHER_CONTROLLER to instruct the
“other controller” to bring the units online.
Note: All partitions on a container must be addressed through the same controller. If
you set
PREFERRED_PATH for one partition, all partitions on that container inherit
the same path.