Configuring an Array
7-32
Compaq Smart Array 5i Plus Controller and Battery Backed Write Cache Enabler User Guide
COMPAQ CONFIDENTIAL
Writer: Amy L. Laffitte File Name: h-ch7 Configuring an Array
Codename: Executor Part Number: 266328-001 Last Saved On: 2/8/02 10:39 AM
•
With a
low
priority setting, a rebuild or expansion takes place only when the
array controller is not busy handling normal I/O requests. This setting has
minimal effect on normal I/O operations. However, there is an increased risk that
data will be lost if another physical drive fails while the rebuild is in progress.
•
With a
high
priority setting, the rebuild or expansion occurs at the expense of
normal I/O operations. Although performance is affected, this setting provides
better data protection because the array is vulnerable to additional drive failures
for a shorter time.
NOTE:
Logical drives can be rebuilt only if they are configured for fault tolerance (RAID 1+0,
5, or ADG). Drive rebuild begins automatically after you have replaced a failed physical drive in
the array.
The accelerator read/write ratio determines the amount of memory allocated to the
read and write caches on the array accelerator. Different applications have different
optimum settings. Some controllers (especially those without battery backed write
cache) do not allow this ratio to be changed.
1.
In the
Logical Configuration View
panel, select the controller that you want to
configure, and then press the
Enter
key.
2.
Select
Controller Settings
from the
Controller Options
panel, and then press
the
Enter
key.
The
Controller Settings
screen is displayed.
Figure 7-23: Controller Settings screen
