Search Appliance SBE
Specifies the minimum and maximum SMB protocols to use when accessing network shares (file:// URLs), i.e. for walking and Results Authorization (here). SMB Min is the minimum SMB protocol (default SMB 2); SMB Max is the maximum SMB protocol (default SMB 3).
Note that this setting only applies if Network Share Access Method is Current and in effect; it also may not appear at all if Current is not supported. See the Network Share Access Method setting (here) for details.