diff --git a/shadowsocks-libev/files/shadowsocks-libev.init-nft b/shadowsocks-libev/files/shadowsocks-libev.init-nft
index 0abc4855d..97740176f 100755
--- a/shadowsocks-libev/files/shadowsocks-libev.init-nft
+++ b/shadowsocks-libev/files/shadowsocks-libev.init-nft
@@ -145,6 +145,20 @@ ss_rules_cb() {
 	fi
 }
 
+ss_redir_ports() {
+	port=$(uci -q get shadowsocks-libev.$1.local_port)
+	server=$(uci -q get shadowsocks-libev.$1.server)
+	disabled=$(uci -q get shadowsocks-libev.$1.disabled)
+	if [ "$disabled" != "1" ] && ([ "$server" = "$2" ] || [ "$2" = "" ]); then
+		if [ "$port" -lt "$min_ss_redir_ports" ]; then
+			min_ss_redir_ports=$port
+		fi
+		if [ "$port" -gt "$max_ss_redir_ports" ]; then
+			max_ss_redir_ports=$port
+		fi
+	fi
+}
+
 ss_rules_nft_gen() {
 	local cfg="ss_rules"
 	local cfgtype