Add missing method for setting encrpted IPv6 address.

* Clean up

Source/MQTTnet.Server/Configuration/ListenModel.cs

@@ -79,8 +79,8 @@ namespace MQTTnet.Server.Configuration
 
             if (IPv4 == "disable")
             {
-                address = null;
-                return false;
+                address = IPAddress.None;
+                return true;
             }
 
             if (IPAddress.TryParse(IPv4, out var ip))
@@ -114,8 +114,8 @@ namespace MQTTnet.Server.Configuration
 
             if (IPv6 == "disable")
             {
-                address = null;
-                return false;
+                address = IPAddress.None;
+                return true;
             }
 
             if (IPAddress.TryParse(IPv6, out var ip))

Source/MQTTnet.Server/Mqtt/MqttServerService.cs

@@ -114,7 +114,7 @@ namespace MQTTnet.Server.Mqtt
 
                 if (_settings.EndpointEncryption.TryReadIPv6(out var address6))
                 {
-                    options.WithEncryptedEndpointBoundIPAddress(address6);
+                    options.WithEncryptedEndpointBoundIPV6Address(address6);
                 }
 
                 if (_settings.Endpoint.Port > 0)

Source/MQTTnet.Server/appsettings.json

@@ -17,7 +17,7 @@
             "IPv4": "localhost",
             "IPv6": "localhost",
             "Port": 8883,
-            "CertificatePath": "/absolute/path/to/certificate"
+            "CertificatePath": "/absolute/path/to/pfx"
         },
         "CommunicationTimeout": 15, /* In seconds */
         "ConnectionBacklog": 0, /* Set 0 to disable */

Source/MQTTnet/Server/MqttServerOptionsBuilder.cs

@@ -75,6 +75,12 @@ namespace MQTTnet.Server
             return this;
         }
 
+        public MqttServerOptionsBuilder WithEncryptedEndpointBoundIPV6Address(IPAddress value)
+        {
+            _options.TlsEndpointOptions.BoundInterNetworkV6Address = value;
+            return this;
+        }
+
         public MqttServerOptionsBuilder WithEncryptionCertificate(byte[] value)
         {
             _options.TlsEndpointOptions.Certificate = value;