User`s guide

Automatic Rebuild
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For more information, see the TPM documentation and online help.
Automatic Rebuild
The RAID controller provides automatic rebuild capabilities in the event of a physical
disk drive failure. The controller performs a rebuild operation automatically when a disk
drive fails and the following conditions are true:
• All system drives that are dependent on the failed disk drive are configured as a
redundant array; RAID 1, RAID 3, RAID 5, or RAID 0+1;
• The Automatic rebuild management controller parameter is enabled;
• The Operational fault management controller parameter is enabled; and
• A replacement drive with a capacity that is at least as large as the consumed
capacity of the failed drive is present in the system.
Note: If a replacement drive of the exact size is not available, the controller selects the
smallest replacement drive found with a capacity that is at least as large as the consumed
capacity of the failed drive. The consumed capacity is the capacity assigned to the
configured system drive(s). If the consumed capacity of the failed disk drive is a
percentage of the total capacity, a larger physical disk drive can be rebuilt with a much
smaller physical disk drive.
During the automatic rebuild process, system activity continues as normal. However,
system performance may be slightly degraded.
Online rebuild The disk drive is in the process of being rebuilt.
(In a RAID 1 or 0+1 array, data is being copied from the mirrored disk drive to the
replacement disk drive. In a RAID 3 or 5 array, data is being regenerated by the exclusive
OR (XOR) algorithm and written to the replacement disk drive.)
Unconfigured This location is unconfigured.
Environmental An environmental device is present at this address.
Table 4-6 Physical Disk Drive States (continued)
State Description