Manage aggregate-level background deduplication on AFF systems
Aggregate-level deduplication eliminates duplicate blocks across volumes belonging to the same aggregate. Beginning with ONTAP 9.3, you can perform aggregate-level deduplication in the background on AFF systems. The feature is enabled by default for all newly created volumes and all upgraded volumes with volume background deduplication turned on.
The operation is triggered automatically when a large enough percentage of the change log has been populated. No schedule or policy is associated with the operation.
Beginning with ONTAP 9.4, AFF users can also run the aggregate-level deduplication scanner to eliminate duplicates of existing data across volumes in the aggregate. You can use the
storage aggregate efficiency cross-volume-dedupe start command with the
-scan-old-data=true option to start the scanner:
cluster-1::> storage aggregate efficiency cross-volume-dedupe start -aggregate aggr1 -scan-old-data true
Deduplication scanning can be time-consuming. You might want to run the operation in off-peak hours.
Aggregate-level background deduplication is sometimes referred to as cross-volume background deduplication.
Manage aggregate-level background deduplication on AFF systems:
If you want to… Use this command
Enable aggregate-level background deduplication
volume efficiency modify -vserver <vserver_name\> -volume <vol_name\> -cross-volume-background-dedupe true
Disable aggregate-level background deduplication
volume efficiency modify -vserver <vserver_name\> -volume <vol_name\> -cross-volume-background-dedupe false
Display aggregate-level background deduplication status
aggregate efficiency cross-volume-dedupe show