Applies to ONTAP 9 7-Mode Transition Tool (7MTT) CIFS/SMB Service principal name (SPN) Description How to set service principal names (SPN) correctly when using a NetBIOS alias. Most commonly an issue...Applies to ONTAP 9 7-Mode Transition Tool (7MTT) CIFS/SMB Service principal name (SPN) Description How to set service principal names (SPN) correctly when using a NetBIOS alias. Most commonly an issue after migration from 7-Mode to ONTAP where old CIFS server name is used as NetBIOS alias for new CIFS server on ONTAP system.