IBM ServeRAID-8 Series, Лучшие практики и информация по обслуживанию

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For more information, see the following RETAIN tip.
Hard Disk Drives rebuild after going defunct and a system restart
http://www-304.ibm.com/systems/support/supportsite.wss/
docdisplay?brandind=5000008&lndocid=MIGR-5072365
(Type
5072365
in the Search field at http://www.ibm.com.)
The Automatic Failover feature and how it affects replaced drives
The Automatic Failover feature of the Adaptec RAID Configuration Utility controls
the rebuilding of a logical drive when a defunct drive is replaced.
Defunct is a
physical-drive state in which the ServeRAID controller cannot communicate
correctly with the drive.
When Automatic Failover is enabled (the default setting), the ServeRAID controller
automatically starts a rebuild operation when a hard disk drive is installed to replace
a defunct drive and no other hot-spare options are defined. Hot spares always have
priority over the Automatic Failover feature.
When Automatic Failover is disabled and a new (never used) hard disk drive is
installed to replace a defunct drive, the new drive status becomes Ready. Then, you
must manually configure the drive for operation. The drive can be used in a new
array or defined as a hot spare. If an array is critical and the drive is defined as a
hot spare, a rebuild operation starts for the drive, if its size qualifies the drive as a
replacement disk.
Attention: When Automatic Failover is disabled, do not replace a defunct hard
disk drive with a hard disk drive that has existing ServeRAID configuration
information (metadata). The ServeRAID controller tries to use the existing
information on the drive to recover the array. The newly installed drive might appear
as part of an incomplete array, or, if the drive is a simple volume or one part of a
mirror, the array might come online. If the newly installed drive is part of a mirror, it
might come online in a Critical state. In some cases, this causes unpredictable
behavior and data corruption.
Important: If Automatic Failover is disabled, before you install a hard disk drive
that has existing ServeRAID configuration information, you must first
initialize the drive to remove the existing configuration information. For
more information, see “Initializing previously used good hard disk
drives” on page 2.
To change the Automatic Failover feature setting, press Ctrl+A when you are
prompted at system startup. From the
Adaptec RAID Configuration Utility menu,
select SerialSelect Utility ; then, select Controller Configuration . You can also
use the arcconf failover command to change the Automatic Failover feature
setting, if you are using firmware version build 15407 or later.
Performance is degraded with multiple ongoing background tasks
The ServeRAID-8 series controllers are designed to run multiple background tasks
at the same time. Background tasks are rebuilds, synchronizations, and copy back
operations. There can be a significant performance impact, to the point of making
the controller unusable, if too many operations are started and you do not balance
the total number of tasks and the priority of those tasks.
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ServeRAID-8 Series: Best Practices and Maintenance Information