Areca ARC-1120 Computer Hardware User Manual


 
INTRODUCTION
21
global hot spare disk drive. To effectively use the global hot
spare feature, you must always maintain at least one drive that
is marked as a global spare.
Important:
The hot spare must have at least the same capacity as the
drive it replaces.
1.4.2 Hot-Swap Disk Drive Support
The SATA controller chip includes a protection circuit that supports
the replacement of SATA hard disk drives without having to shut
down or reboot the system. A removable hard drive tray can de-
liver “hot swappable” fault-tolerant RAID solutions at prices much
less than the cost of conventional SCSI hard disk RAID control-
lers. This feature provides advanced fault tolerant RAID protection
and “online” drive replacement.
1.4.3 Auto Declare Hot-Spare
If a disk drive is brought online into a system operating in de-
graded mode, The SATA RAID controllers will automatically de-
clare the new disk as a spare and begin rebuilding the degraded
volume. The Auto Declare Hot-Spare function requires that the
smallest drive contained within the volume set in which the failure
occurred.
In the normal status, the newly installed drive will be recongured
an online free disk. But, the newly-installed drive is automatically
assigned as a hot spare if any hot spare disk was used to rebuild
and without new installed drive replaced it. In this condition, the
Auto Declare Hot-Spare status will disappeared if the RAID sub-
system has since powered off/on.
The Hot-Swap function can be used to rebuild disk drives in arrays
with data redundancy such as RAID level 1, 1E, 3, 5, and 6.