Rebuild; Hot Spare Rebuild; Hot Swap Rebuild - NEC EXPRESS5800 User Manual

3.10 Rebuild

The rebuild feature can recover redundancy if a single HDD is defected in RAIL level 1, 10 or
5.
During rebuild, data read/write is enabled. However, the redundancy is lost until the rebuild
operation is completed.
If an HDD is defected, logical drives are entered into the critical state, of which you are notified.
IMPORTANT: Note that load is applied to the system to
decrease its processing rate during rebuild.

3.10.1 Hot Spare Rebuild

If a redundant logical drive is degraded, hot spare rebuild is done under where all the following
conditions match.
Spare drives are set.
Spare drives have capacity set
properly.
When the above conditions are met, host spare rebuild is started automatically. (The physical
drives that is not configured to any disk arrays cannot be used as spare drives.)

3.10.2 Hot Swap Rebuild

Hot swap rebuild is done when the following conditions are met.
Auto Rebuild is enabled.
A defected physical drive is
replaced with a new HDD on
the same slot.
If the above conditions are met, hot swap rebuild is started automatically.
Spare drives of either of the following types are required:
Spare drives set to global
•
Spare drives dedicated for logical drive entered into degraded
•
state
Spare drives should have capacities equal to or larger than
those of defected physical drives.
Enable Auto Rebuild should be checked in the Settings screen
appearing in the Background Activities tab of subsystem ST
EX4650EL. See the description of the Background Activities tab in
"3.5.1 Subsystem (ST EX4650EL) icon" for details.
The new HDD should have a capacity equal to or larger than that
of the defected physical drive.
- -
50