User Guide

Chapter 5: Monitor and Manage
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4. Click the Activation button.
In a few moments, the logical drive status goes from offline to critical. Critical
status allows you to access your data and rebuild the logical drive.
Logical Drive Critical / Offline
A fault-tolerant logical drive—RAID 1 or 10—goes critical when a disk drive is
removed or fails. Due to the fault tolerance of the logical drive, the data is still
available and online. However, once the logical drive goes critical, it has lost its
fault tolerance and performance may be adversely affected.
If the fault was caused by a failed disk 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.
A non-fault tolerant logical drive—RAID 0—goes offline when a disk drive is
removed or fails. Since the logical drive 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 logical drive is lost. You must replace
the failed drive. Then, if the logical drive had more than one disk drive, delete the
logical drive, and re-create it. Restore the data from a backup source.
When a Disk Drive Fails
The following will occur when a disk drive fails or goes offline:
• The ATI SB600 Controller’s audible alarm, if enabled, will sound
• WebPAM reports the condition in Tree View, with popup messages and, if
Event Notification is set up, email messages
• If you have a RAID 1 logical drive with a hot spare drive properly configured,
the logical drive will automatically rebuild itself using the spare drive