If you delete a backup copy of a LUN that was already backed up by another Snapshot copy, you get an error message saying that the Snapshot copy is busy and cannot be deleted. In this case, you need to delete the most recent backup copy before the older backup can be deleted.
To see if you have busy Snapshot copies, you can view your Snapshot copies in FilerView or use the storage system
snap list command. For more information about deleting busy Snapshot copies, see
Data ONTAP Block Access Management Guide for iSCSI and FC for your version of Data ONTAP.
Note: To avoid this situation, ensure that you do not make backup copies of LUNs that are already backed up by Snapshot copies (for example, during a verification or while archiving from a LUN backed by a Snapshot copy).