1.NORMAL The NORMAL state is displayed when everything is functioning correctly.
2.CRITICAL The CRITICAL state is displayed when the array is no longer redundant (fault tolerant) because of one or more disk fail- ures. Arrays can still be read and written to, but the data is no longer protected should another drive fail.
3.OFFLINE The OFFLINE state is displayed when arrays cannot be read or written to because of one or more disk failures.
•For RAID1 and RAID5 (redundant arrays), the CRITICAL state is dis- played when a single disk fails.
•For RAID1n, RAID10, RAID10n, or RAID50 (array types with multi- ple redundancies), the CRITICAL state is displayed if a single disk fails in any one of those sets.
•For Volume and RAID0, the OFFLINE state is displayed when a single disk fails.
•For RAID1 and RAID5 (redundant arrays), the OFFLINE state is dis- played when two or more disks fail.
•For RAID1n, RAID10, RAID10n (array types with multiple redundan- cies), the OFFLINE state is displayed if all disks in a set fail.
•For RAID50 (an array type with multiple redundancies), the OFFLINE state is displayed if two or more disks fail within the same set. For example, RAID50 is a stripe of RAID5 sets. If a RAID50 set contains three RAID5 sets, each RAID5 set can have up to one disk failure and the RAID50 array state shows as CRITICAL. If a fourth disk fails, the state of the RAID50 array changes to OFFLINE. If two drives fail on one of the RAID5 sets, the state of the RAID50 array changes to
OFFLINE.
More than one array can be created using the same set of disks. If you dis- connect a disk that belongs to more than one array, only the arrays that try to access the disk and receive I/O errors report the failure. For example: you have two arrays, both RAID5 sets, and both use disk 4. If a system being used by array 1 receives an I/O error when trying to communicate with disk 4, the state of array 1 will change to CRITICAL. However, the state of array 2 using disk 4 will not change to CRITICAL until an I/O error is reported. If systems using array 1 are not communicating with the failed disk, the state of array 1 still displays as NORMAL. If you perform
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