Revise dnsagent service and its default port

config/config_defaults.go

@@ -735,7 +735,7 @@ const CGRATES_CFG_JSON = `
 	"enabled": false,											// enables the DNS agent: <true|false>
 	"listeners":[
 		{
-			"address": "127.0.0.1:2053",							// address where to listen for DNS requests <x.y.z.y:1234>
+			"address": "127.0.0.1:53",							// address where to listen for DNS requests <x.y.z.y:1234>
 			"network": "udp"										// network to listen on <udp|tcp|tcp-tls>
 		}
 	],

config/config_it_test.go

@@ -653,6 +653,10 @@ func testCGRConfigReloadDNSAgent(t *testing.T) {
 				Address: ":2053",
 				Network: "udp",
 			},
+			{
+				Address: ":2054",
+				Network: "tcp",
+			},
 		},
 		SessionSConns: []string{utils.ConcatenatedKey(utils.MetaInternal, utils.MetaSessionS)},
 		// Timezone          string

config/config_json_test.go

@@ -1015,7 +1015,7 @@ func TestDNSAgentJsonCfg(t *testing.T) {
 		Listeners: &[]*ListenerJsnCfg{
 			{
 				Network: utils.StringPointer("udp"),
-				Address: utils.StringPointer("127.0.0.1:2053"),
+				Address: utils.StringPointer("127.0.0.1:53"),
 			},
 		},
 		Sessions_conns:     &[]string{utils.ConcatenatedKey(utils.MetaInternal)},