Disk scrubbing means checking the disk blocks of all disks on the storage system for media errors and parity consistency. If Data ONTAP finds media errors or inconsistencies, it fixes them by reconstructing the data from other disks and rewriting the data. Disk scrubbing reduces the chance of potential data loss as a result of media errors during reconstruction.
You can use the Disk Report page to scrub RAID groups. The RAID type of the group affects when you can run a scrub operation:
If RAID-4 is enabled, Data ONTAP scrubs a RAID group only when all the group's disks are operational.
If RAID-DP is enabled, Data ONTAP can carry out a scrub even if one disk in the RAID group has failed.
To start a disk scrub, select the checkbox for the RAID group you want to scrub, then click Start Scrub.
The progress of the scrub is displayed as part of the status for the RAID group. Click Refresh to update the scrub status.
To stop a disk scrub, select the checkbox for the RAID group running a scrub that you want to stop, then click Stop Scrub.
Rather than stopping Data ONTAP from checking and correcting parity, you can suspend checking for any period of time and resume it later, at the same offset when you suspended the scrub.
To suspend disk scrubbing, select the checkbox for the RAID group running a scrub that you want to suspend, then click Suspend Scrub.To resume a suspended disk scrub, select the checkbox for the RAID group with a suspended scrub that you want to resume, then click Resume Scrub.