384Chapter 10: TroubleshootingCritical & Offline Disk ArraysA fault-tolerant disk array—RAID 1, 1E, 5, 10, and 50—goes critical when a diskdrive is removed or fails. A RAID 6 or 60 disk array—goes degraded when a diskdrive is removed or fails and critical when two disk drives are removed of fail.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 faulttolerance, and performance may be adversely affected.If the fault was caused by a failed drive that was removed, the drive must bereplaced by another drive, either identical or larger, in order for the RAID systemto rebuild and restore optimal configuration.If your fault-tolerant disk array – RAID 1, 1E, 5, 6, 10, 50, and 60 – goes offline,contact ASUS Technical Support. See page 402.WarningTake no further corrective action until you have consulted withASUS Technical Support.A non-fault tolerant disk array—RAID 0—goes offline when a disk drive isremoved or fails. Since the disk array is not fault tolerant, the data stored in thedisk array is no longer accessible.If one disk drive fails, all of the data on the disk array is lost. You must replace thefailed drive. Then, if the disk array had more than one disk drive, delete the diskarray and re-create it. Restore the data from a backup source.When a Physical Drive FailsASUS Storage provides both audible and visual indicators to alert you of a diskdrive failure. The following will occur when a disk drive fails or goes offline:• The Global RAID Status LED changes from green to amber.Figure 14. ASUS Storage front panel LEDsPowerGlobal Enclosure StatusGlobal RAID Status
