Applies to ONTAP 9 Issue Offlining a complete empty aggregate fails with: Error: Failed to take aggregate "MyAggr" offline. Reason: Aggregate is in use by other operations. () Event log shows notice: ...Applies to ONTAP 9 Issue Offlining a complete empty aggregate fails with: Error: Failed to take aggregate "MyAggr" offline. Reason: Aggregate is in use by other operations. () Event log shows notice: Wed Mar 05 08:24:00 +0100 [MyCluster-01: config_async_0: raid.offline.busy:notice]: Active operations in progress on aggregate MyAggr: WAFL open files exist.