Why is the rebalancing not performed and the content of…

View Exhibit1 to examine the CRS11G disk group when all the disks are online.
View Exhibit2 to examine the CRS11G disk group when one disk is offline.
Why is the rebalancing not performed and the content of the disk group not empty in Exhibit2?
ASM-disk-group-1 (exhibit):

ASM-disk-group-2 (exhibit):

View Exhibit1 to examine the CRS11G disk group when all the disks are online.
View Exhibit2 to examine the CRS11G disk group when one disk is offline.
Why is the rebalancing not performed and the content of the disk group not empty in Exhibit2?
ASM-disk-group-1 (exhibit):

ASM-disk-group-2 (exhibit):

A.
Because the disk group is created with NORMAL redundancy

B.
Because the disk repair time attribute is set to a nonzero value

C.
Because the mirrored extents cannot be rebalanced across the other three disks

D.
Because the other three disks have 60% free space, the disk rebalancing is delayed

Explanation:
Key points:
1. The COMPATIBILITY.ASM>=11.1 and COMPATIBILITY.RDBMS>=11.1
2. The DISK_REPAIR_TIME is set to non-zero. by default it is 3.6hr.
Note: To use this feature, the disk group compatibility attributes must be set to 11.1 or higher. For more
information, refer to “Disk Group Compatibility”.
Oracle ASM fast resync keeps track of pending changes to extents on an OFFLINE disk during an outage. The
extents are resynced when the disk is brought back online.
By default, Oracle ASM drops a disk in 3.6 hours after it is taken offline. You can set the DISK_REPAIR_TIME
disk group attribute to delay the drop operation by specifying a time interval to repair the disk and bring it back
online.



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