To rebalance ASM (Automatic Storage Management) disks in Oracle, you can use the ALTER DISKGROUP command in SQL*Plus or Oracle SQL Developer. Rebalancing typically occurs after disk additions, removals, or other changes to the ASM disk group.
ALTER DISKGROUP <diskgroup_name> REBALANCE;
Where <diskgroup_name> is the name of the ASM disk group that you want to rebalance.
Example:
ALTER DISKGROUP DATA REBALANCE;
This will trigger the rebalancing process for the DATA disk group.
To Monitor the progress of ASM rebalancing , query v$asm_operation table
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