Areca ARC-1880 Series, Руководство пользователя

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APPENDIX
186
to rebuild and without new installed drive replaced it. In this
condition, the Auto Declare Hot-Spare status will be disappeared
if the RAID subsystem has since powered off/on.
The Hot-Swap function can be used to rebuild disk drives in ar-
rays with data redundancy such as RAID level 1, 1E, 3, 5, 6, 10,
30, 50 and 60.
• Auto Rebuilding
If a hot spare is available, the rebuild starts automatically when a
drive fails. The RAID controllers automatically and transparently
rebuild failed drives in the background at user-definable rebuild
rates.
If a hot spare is not available, the failed disk drive must be re-
placed with a new disk drive so that the data on the failed drive
can be automatically rebuilt and so that fault tolerance can be
maintained.
RAID controllers will automatically restart the system and re-
building process if the system is shut down or powered off abnor-
mally during a reconstruction procedure condition.
When a disk is hot swapped, although the system is functionally
operational, the system may no longer be fault tolerant. Fault
tolerance will be lost until the removed drive is replaced and the
rebuild operation is completed.
During the automatic rebuild process, system activity will contin-
ue as normal, however, the system performance and fault toler-
ance will be affected.
•
Adjustable Rebuild Priority
Rebuilding a degraded volume incurs a load on the RAID sub-
system. The RAID controllers allow the user to select the rebuild
priority to balance volume access and rebuild tasks appropriately.
The Background Task Priority is a relative indication of how much
time the controller devotes to a background operation, such as
rebuilding or migrating.