server min protocol

This setting controls the minimum protocol version that the server will allow the client to use.
Normally this option should not be set as the automatic negotiation phase in the SMB protocol takes care of choosing the appropriate protocol unless you have legacy clients which are SMB1 capable only.
See server max protocol for a full list of available protocols.

Example: NT1

Supported on: At least Microsoft Windows 7 or Windows Server 2008 family

server min protocol

Registry HiveHKEY_LOCAL_MACHINE
Registry PathSoftware\Policies\Samba\smb_conf\server min protocol
Value Nameserver min protocol
Value TypeREG_SZ
Default ValueSMB2_02

samba.admx

Administrative Templates (Computers)