Logical corruption checks on disk, disk scrubbing - ASM

 

12c Database : ASM Enhancements : Logical corruption checks on disk, disk scrubbing

ASM 12c provides proactive scrubbing capabilities on disks that check for logical corruptions and automatically repair them where possible. 

SQL> alter diskgroup DG1 scrub repair;
Diskgroup altered.

SQL> alter diskgroup DG1 scrub file '+DATA_DISK/Geek DBA12C/DATAFILE/system.254.939393617' repair wait;
Diskgroup altered.

SQL> alter diskgroup DG1 scrub disk DATA_DISK1 repair power max force;
Diskgroup altered

REPAIR:  If the repair option is not specified, ASM only check and report logical corruption
POWER:  LOW, HIGH, or MAX.  If power is not specified, the scrubbing power is controlled based on the system I/O load
FORCE:  Command is processed immediately regarless of system load

Two ways of scrubbing:  On-demand  by administrator on specific area as like above, Occur as part of rebalance operation if disk attribute content.check=TRUE mentioned at disk level.

SQL> alter diskgroup DG1 attribute 'content.check' = 'TRUE';
Diskgroup altered.