You can configure default values for various TLS properties in the mf-server.dat file. When a TLS-enabled listener is started, the file is checked for default values. If the listener does not specify a value for a property, the value from the file is used instead.
The mf-server.dat file is located in the %ProgramFiles(x86)%\Micro Focus\Visual COBOL\bin directory (Windows), or $COBDIR/bin folder (UNIX).
See Specifying a Server Protocol and Cipher Suite Preference for more information.
[TLS] ; The separator used for passwords if multiple certificates are specified ;password separator= ; The TLS protocols field specifies the list of protocols to be used and ; the order of preference in which they are to be used ;protocols= ; The Cipher Suites field specifies the list of ciphers to be used in ; order of preference of use. ;cipher suites= ; The TLS 1.3 specific cipher suites list ;TLS1.3 cipher suites= ; The minimum size in bits of the modulus length of the Diffie-Hellman (DH) group ; that is used to negotiate with connecting peers when using DH cipher suites. ;min dh size= ; The Cipher Groups (previously 'ECC curves') enable you to specify the list of ; ciphers to be used and the order of preference in which they are to be used. ;cipher groups= ; Set whether the middlebox workaround is disabled. Any setting here overwrites any value ; set in a listener. ; Values: "disable" or "enable" ;middlebox workaround= ; Set whether the server enforces all clients to use its cipher list ; Values: "yes"/"1", "no"/"0" ; Any setting here overwrites any value set in a listener. ;honor server cipher list=