HP Array Configuration Utility 71
Setting the preferred path mode
The preferred path mode determines how I/O traffic to the logical drives is managed on controllers that
are in an active/active configuration.
•
In Automatic mode, the storage system automatically selects a suitable path for I/O traffic to each
logical drive depending on the host I/O patterns at the time. Because the optimum path can vary
with time, I/O traffic for any given logical drive can be directed through either controller.
•
In Manual mode, all I/O traffic to a given logical drive is directed through a designated controller.
In this case, you must also specify the preferred controller for each logical drive ("
Assigning a
redundant controller to a logical drive
" on page
71
).
Syntax:
<target> modify [preferredpathmode=automatic|manual|?]
where
<target>
is a redundant controller.
Example command:
controller ch="lab 3" modify ppm=manual
Assigning a redundant controller to a logical drive
When you have set the preferred path mode ("
Setting the preferred path mode
" on page
71
) in a
redundant system to Manual, you must use the
chassisslot
command to assign each logical drive in
the system to one of the redundant controllers.
Syntax:
<target> modify [chassisslot=#|?]
where
<target>
is a valid logical drive on a controller that is in an active/active configuration and #
denotes the chassis slot number of the redundant controller. (To obtain the chassis slot number, use the
show
command on the controller.)
Example command:
controller ch="lab 3" ld 1 modify chs=2
Disabling a redundant controller
This command disables a redundant controller that is in an Active-Standby configuration.
IMPORTANT:
The redundant controller cannot be re-enabled after you have disabled it.
Syntax:
<target> modify redundantcontroller=disable
where
<target>
is a controller that has an enabled redundant controller.
Example command:
=> ctrl ch="redundant Lab4" modify rc=disable
Changing the Rebuild Priority setting
The Rebuild Priority setting determines the urgency with which the controller treats an internal command to
rebuild a failed logical drive.
•
At the low setting, normal system operations take priority over a rebuild.
