Hi, sorry not exactly sure of what you are trying to achieve...
- Deletion of unused storage (or a plan to delete)
With ONTAP 9 there is a new volume autosize option that allows the size of the volume to shrink (as well as grow). Please see the Logical Storage Management Guide page 15: https://library.netapp.com/ecm/ecm_download_file/ECMLP2492715. The command is...
volume autosize -vserver vserver_name vol_name -mode grow_shrink
You could therefore leave the volumes to manage their size automatically, just monitoring the events in OnCommand Unified Manager (OCUM) or similar. There is another thread about monitoring EMS event in OnCommand: http://community.netapp.com/t5/OnCommand-Storage-Management-Software-Discussions/Can-t-Subscribe-to-an-EMS-Event-in-OCUM/m-p/132274#M24009
- Re-Allocation of storage (or a plan to re-allocate)
Do you mean setting up a schedule to implement a reallocate scan to better optimise the layout of blocks in the volume/aggregate? See volume reallocation and storage aggregate reallocation in the commands guide: https://library.netapp.com/ecm/ecm_download_file/ECMLP2573244.
OCUM also has some capacity reports that may be of assistance. See NetApp Software Download page (Windows link here: https://mysupport.netapp.com/NOW/download/software/oncommand_cdot_win/7.1/)
Let me know if you need any more assistance.
Cheers,
Grant.