IBM System Storage DS3000, Programming Manual

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The
addDrives
parameter supports both high-capacity and low-capacity drive expansion enclosures. A
high-capacity drive expansion enclosure has drawers that hold the drives. The drawers slide out of the
drive expansion enclosure to provide access to the drives. A low-capacity drive expansion enclosure does
not have drawers. For a high-capacity drive expansion enclosure, you must specify the identifier (ID) of
the drive expansion enclosure, the ID of the drawer, and the ID of the slot in which a drive resides. For a
low-capacity drive expansion enclosure, you need to specify the ID of the drive expansion enclosure and
the ID of the slot in which a drive resides. For a low-capacity drive expansion enclosure, an alternative
method for identifying a location for a drive is to specify the ID of the drive expansion enclosure, set the
ID of the drawer to 0, and specify the ID of the slot in which a drive resides.
Cache Flush Modifier
Valid values for the cache flush modifier are listed in this table.
Value Description
Immediate Data is flushed as soon as it is placed into the cache.
250
Data is flushed after 250 ms.
500
Data is flushed after 500 ms.
750
Data is flushed after 750 ms.
1
Data is flushed after 1 s.
1500
Data is flushed after 1500 ms.
2
Data is flushed after 2 s.
5
Data is flushed after 5 s.
10
Data is flushed after 10 s.
20
Data is flushed after 20 s.
60
Data is flushed after 60 s (1 min.).
120
Data is flushed after 120 s (2 min.).
300
Data is flushed after 300 s (5 min.).
1200
Data is flushed after 1200 s (20 min.).
3600
Data is flushed after 3600 s (1 hr).
Infinite
Data in cache is not subject to any age or time constraints. The
data is flushed based on other criteria that are managed by the
controller.
Cache Without Battery Enabled
Write caching without batteries enables write caching to continue if the controller batteries are completely
discharged, not fully charged, or not present. If you set this parameter to
TRUE
without an uninterruptible
power supply (UPS) or other backup power source, you can lose data if the power to the storage
subsystem fails. This parameter has no effect if write caching is disabled.
Modification Priority
Modification priority defines the amount of system resources that are used when modifying logical drive
properties. If you select the highest priority level, the logical drive modification uses the most system
resources, which decreases the performance for host data transfers.
Chapter 3. Script Commands
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