Promise Technology VTrak 15110 - Manual (Page 242)

VTrak 15110 User Manual
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Critical & Offline Disk Arrays
A fault-tolerant disk array—RAID 1, 3, 5, 10 and 50—goes critical when a drive is
removed or fails. Due to the fault tolerance of the disk array, the data is still
available and online. However, once the disk array goes critical, the disk array
has lost its fault tolerance, and performance may be adversely affected.
If the fault was caused by a failed drive that was removed, the drive must be
replaced by another drive, either identical or larger, in order for the RAID system
to rebuild and restore optimal configuration.
If your fault-tolerant disk array goes offline, go to the Promise website
(www.promise.com) and download a document called Array Recovery
Procedure.
A non-fault tolerant disk array—RAID 0—goes offline when a drive is removed or
fails. Since the disk array is not fault tolerant, the data stored in the disk array is
no longer accessible.
If one disk drive fails, all of the data on the disk array is lost. You must replace the
failed drive. Then, if the disk array had more than one disk drive, delete the disk
array and re-create it. Restore the data from a backup source.
When a Disk Drive Fails
VTrak provides both audible and visual indicators to alert you of a disk drive
failure. The following will occur when a disk drive fails or goes offline:
•
The Disk Array LED changes from green to amber
• The Disk Carrier Status LED changes from green to red
• The audible alarm repeatedly sounds two short beeps
• WebPAM PRO and the CLU report the condition
Rebuild
Normally, the disk array will begin rebuilding automatically. You can access your
disk array during this time but read/write performance might be slower than
normal.
•
If a hot spare drive is provided and enabled, the controller will activate the
hot spare and rebuild disk array information and data to it.
• If there is no hot spare drive available, the controller will wait until a
replacement disk drive is installed. The disk array will remain Critical.