Depending on how much data is stale, the operation may require additional time to complete. You can monitor the operation's progress using the Pending Operations link from the Disk Group home page.

The value that you set for Rebalance Power using ASM_POWER_LIMIT must be a whole number. The text on the page describes how the value of Rebalance Power affects the fast mirror resync operation. If the ASM_POWER_LIMIT is set to 0, then Oracle ASM does not perform automatic rebalance. For information about rebalance power settings and the ASM_POWER_LIMIT initialization parameter, refer to "ASM_POWER_LIMIT".

By default, the Rebalance Power value uses the value of the ASM_POWER_LIMIT initialization parameter.

Oracle Enterprise Manager displays an Offline Confirmation page and the text on this page explains that after Oracle Enterprise Manager takes the selected disks offline, the Oracle ASM instance waits for the time interval that is specified by the value that you have set for the DISK_REPAIR_TIME initialization parameter before Oracle ASM drops the disks. During the disk repair time period, you can repair the disks and then place them back online. For each disk that you successfully place online, the pending drop operation is canceled and a resynchronization operation begins.

If you have set DISK_REPAIR_TIME to a large value, for example, greater than one day, then this increases the possibility of data loss. This is because the files in the disk group are protected with a lower degree of redundancy during this period.

Click Yes on the Oracle Enterprise Manager Conformation dialog to begin the offline processing or click No to stop the operation. You can also click Show SQL to see the SQL that Oracle Enterprise Manager uses for the offline operation.