diff --git a/package/luci/files/luci/model/cbi/smartdns/smartdns.lua b/package/luci/files/luci/model/cbi/smartdns/smartdns.lua
index 3f2ead4..0822c41 100644
--- a/package/luci/files/luci/model/cbi/smartdns/smartdns.lua
+++ b/package/luci/files/luci/model/cbi/smartdns/smartdns.lua
@@ -80,12 +80,14 @@ o.rempty      = true
 ---- rr-ttl-min
 o = s:taboption("settings", Value, "rr_ttl_min", translate("Domain TTL Min"), translate("Minimum TTL for all domain result."))
 o.rempty      = true
+o.placeholder = "300"
+o.default     = 300
+o.optional    = true
 
 ---- rr-ttl-max
 o = s:taboption("settings", Value, "rr_ttl_max", translate("Domain TTL Max"), translate("Maximum TTL for all domain result."))
 o.rempty      = true
 
-
 ----- custom settings
 custom = s:taboption("custom", Value, "Custom Settings",
 	translate(""), 
@@ -129,16 +131,17 @@ end
 
 ---- name
 s:option(Value, "name", translate("DNS Server Name"), translate("DNS Server Name"))
+
 ---- IP address
 o = s:option(Value, "ip", translate("ip"), translate("DNS Server ip"))
 o.datatype = "ipaddr"
 o.rmempty = false 
 ---- port
 o = s:option(Value, "port", translate("port"), translate("DNS Server port"))
-o.placeholder = 53
-o.default     = 53
+o.placeholder = "default"
 o.datatype    = "port"
-o.rempty      = false
+o.rempty      = true
+
 ---- type
 o = s:option(ListValue, "type", translate("type"), translate("DNS Server type"))
 o.placeholder = "udp"
diff --git a/package/openwrt/files/etc/init.d/smartdns b/package/openwrt/files/etc/init.d/smartdns
index 11e55b8..088cf25 100644
--- a/package/openwrt/files/etc/init.d/smartdns
+++ b/package/openwrt/files/etc/init.d/smartdns
@@ -130,8 +130,10 @@ load_server()
 {
 	local section="$1"
 	local ADDITIONAL_ARGS=""
+	local DNS_ADDRESS=""
+
 	config_get_bool "enabled" "$section" "enabled" "1"
-	config_get "port" "$section" "port" "53"
+	config_get "port" "$section" "port" ""
 	config_get "type" "$section" "type" "udp"
 	config_get "ip" "$section" "ip" ""
 	config_get "blacklist_ip" "$section" "blacklist_ip" "0"
@@ -141,7 +143,7 @@ load_server()
 		return
 	fi
 
-	if [ -z "$port" ] || [ -z "$ip" ] || [ -z "$type" ]; then
+	if [ -z "$ip" ] || [ -z "$type" ]; then
 		return
 	fi
 
@@ -166,7 +168,13 @@ load_server()
 		ADDITIONAL_ARGS="$ADDITIONAL_ARGS -check-edns"
 	fi
 
-	conf_append "$SERVER" "$ip:$port $ADDITIONAL_ARGS"
+	if [ ! -z "$port" ]; then
+		DNS_ADDRESS="$ip:$port"
+	else
+		DNS_ADDRESS="$ip"
+	fi
+
+	conf_append "$SERVER" "$DNS_ADDRESS $ADDITIONAL_ARGS"
 }
 
 load_service() {
@@ -256,7 +264,7 @@ load_service() {
 	config_get "old_port" "$section" "old_port" "0"
 	config_get "old_enabled" "$section" "old_enabled" "0"
 
-	if [ "$old_redirect" != "$redirect" ] || [ "$old_port" != "$SMARTDNS_PORT" ] || [ "$old_enabled" = "1" ]; then
+	if [ "$old_redirect" != "$redirect" ] || [ "$old_port" != "$SMARTDNS_PORT" ] || [ "$old_enabled" = "1" -a "$enabled" = "0" ]; then
 		if [ "$old_redirect" != "none" ]; then
 			if [ "$old_port" != "0" ]; then
 				clear_iptable "$old_port" "$ipv6_server"