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SAS to SAS/SATA RAID Subsystem
1.4 High Availability
1.4.1 Creating Hot Spares
A hot spare drive is an unused online available drive, which is ready to replace a failed
disk drive. In a RAID level 1, 10, 3, 5, 6, 30, 50, or 60 Raid Set, any unused online
available drive installed but not belonging to a Raid Set can be defined as a hot spare
drive. Hot spares permit you to replace failed drives without powering down the system.
When the RAID subsystem detects a drive failure, the system will do automatic and
transparent rebuild using the hot spare drives. The Raid Set will be reconfigured and
rebuilt in the background while the RAID subsystem continues to handle system request.
During the automatic rebuild process, system activity will continue as normal, however,
the system performance and fault tolerance will be affected.
IMPORTANT: The hot spare must have at least the same or more
capacity as the drive it replaces.
1.4.2 Hot-Swap Disk Drive Support
The RAID subsystem has built-in protection circuit to support the replacement of
SATA II hard disk drives without having to shut down or reboot the system. The
removable hard drive tray can deliver "hot swappable" fault-tolerant RAID solution at a
price much less than the cost of conventional SCSI hard disk RAID subsystems. This
feature is provided in the RAID subsystem for advance fault tolerant RAID protection and
"online" drive replacement.
1.4.3 Hot-Swap Disk Rebuild
The Hot-Swap feature can be used to rebuild Raid Sets with data redundancy such as
RAID level 1, 10, 3, 5, 6, 30, 50 and 60. If a hot spare is not available, the failed disk
drive must be replaced with a new disk drive so that the data on the failed drive can
be rebuilt. If a hot spare is available, the rebuild starts automatically when a drive
fails. The RAID subsystem automatically and transparently rebuilds failed drives in the
background with user-definable rebuild rates. The RAID subsystem will automatically
continue the rebuild process if the subsystem is shut down or powered off abnormally
during a reconstruction process.
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User Manual
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