You must release the persistent reservations on all array LUNs assigned to a Data ONTAP system before removing the system from service.
When you assign Data ONTAP ownership of an array LUN, Data ONTAP places persistent reservations (ownership locks) on that array LUN to identify which Data ONTAP system owns the LUN. If you want the array LUNs to be available for use by other types of hosts, you must remove the persistent reservations that Data ONTAP put on those array LUNs; some arrays do not allow you to destroy a reserved LUN if you do not remove the ownership and persistent reservations that Data ONTAP wrote to that LUN.
For example, the Hitachi USP storage array does not have a user command for removing persistent reservations from LUNs. If you do not remove persistent reservations through Data ONTAP before removing the Data ONTAP system from service, you must call Hitachi technical support to remove the reservations.
Contact technical support for instructions about how to remove persistent reservations from LUNs before removing a Data ONTAP system from service.