diff --git a/mptcp/files/usr/share/omr/post-tracking.d/post-tracking b/mptcp/files/usr/share/omr/post-tracking.d/post-tracking
index 2459dd04c..6300f1640 100755
--- a/mptcp/files/usr/share/omr/post-tracking.d/post-tracking
+++ b/mptcp/files/usr/share/omr/post-tracking.d/post-tracking
@@ -79,7 +79,7 @@ set_server_default_route() {
 		multipath_config_route=$(uci -q get openmptcprouter.$OMR_TRACKER_INTERFACE.multipath)
 		[ -z "$multipath_config_route" ] && multipath_config_route=$(uci -q get network.$OMR_TRACKER_INTERFACE.multipath || echo "off")
 		[ "$(uci -q get openmptcprouter.$OMR_TRACKER_INTERFACE.multipathvpn)" = "1" ] && multipath_config_route="$(uci -q get openmptcprouter.ovpn${OMR_TRACKER_INTERFACE}.multipath || echo "off")"
-		if [ "$serverip" != "" ] && [ "$OMR_TRACKER_DEVICE_GATEWAY" != "" ] && [ "$(ip route show dev $OMR_TRACKER_DEVICE metric 1 | grep $serverip | grep $OMR_TRACKER_DEVICE_GATEWAY)" = "" ] && [ "$multipath_config_route" != "off" ]; then
+		if [ "$serverip" != "" ] && [ "$OMR_TRACKER_DEVICE_GATEWAY" != "" ] && [ -n "$OMR_TRACKER_DEVICE" ] && [ "$(ip route show dev $OMR_TRACKER_DEVICE metric 1 | grep $serverip | grep $OMR_TRACKER_DEVICE_GATEWAY)" = "" ] && [ "$multipath_config_route" != "off" ]; then
 			[ "$(uci -q get openmptcprouter.settings.debug)" = "true" ] && _log "Set server $server ($serverip) default route via $OMR_TRACKER_DEVICE_GATEWAY"
 			if [ "$(ip r show $serverip | grep nexthop)" != "" ]; then
 				ip r delete $serverip >/dev/null 2>&1
@@ -101,7 +101,7 @@ set_server_default_route6() {
 		multipath_config_route=$(uci -q get openmptcprouter.$OMR_TRACKER_INTERFACE.multipath)
 		[ -z "$multipath_config_route" ] && multipath_config_route=$(uci -q get network.$OMR_TRACKER_INTERFACE.multipath || echo "off")
 		[ "$(uci -q get openmptcprouter.$OMR_TRACKER_INTERFACE.multipathvpn)" = "1" ] && multipath_config_route="$(uci -q get openmptcprouter.ovpn${OMR_TRACKER_INTERFACE}.multipath || echo "off")"
-		if [ "$serverip" != "" ] && [ "$OMR_TRACKER_DEVICE_GATEWAY6" != "" ] && [ "$(ip -6 route show dev $OMR_TRACKER_DEVICE metric 1 | grep $serverip | grep $OMR_TRACKER_DEVICE_GATEWAY6)" = "" ] && [ "$multipath_config_route" != "off" ]; then
+		if [ "$serverip" != "" ] && [ "$OMR_TRACKER_DEVICE_GATEWAY6" != "" ] && [ -n "$OMR_TRACKER_DEVICE" ] && [ "$(ip -6 route show dev $OMR_TRACKER_DEVICE metric 1 | grep $serverip | grep $OMR_TRACKER_DEVICE_GATEWAY6)" = "" ] && [ "$multipath_config_route" != "off" ]; then
 			[ "$(uci -q get openmptcprouter.settings.debug)" = "true" ] && _log "Set server $server ($serverip) default route via $OMR_TRACKER_DEVICE_GATEWAY6"
 			if [ "$(ip -6 r show $serverip | grep nexthop)" != "" ]; then
 				ip -6 r delete $serverip >/dev/null 2>&1
@@ -166,7 +166,7 @@ set_routes_intf() {
 		if [ -z "$interface_gw" ]; then
 			interface_gw=$(ubus call network.interface.${INTERFACE}_4 status 2>/dev/null | jsonfilter -q -l 1 -e '@.inactive.route[@.target="0.0.0.0"].nexthop' | tr -d "\n")
 		fi
-		#if [ "$interface_gw" != "" ] && [ "$interface_if" != "" ] && [ "$(ip route show $serverip | grep $interface_if)" = "" ]; then
+		#if [ "$interface_gw" != "" ] && [ "$interface_if" != "" ] && [ -n "$serverip" ] && [ "$(ip route show $serverip | grep $interface_if)" = "" ]; then
 		if [ "$interface_gw" != "" ] && [ "$interface_if" != "" ] && [ -z "$(echo $interface_gw | grep :)" ]; then
 			if [ "$multipath_config_route" = "master" ]; then
 				weight=10
@@ -232,7 +232,7 @@ set_routes_intf6() {
 		if [ -z "$interface_gw" ]; then
 			interface_gw=$(ubus call network.interface.${INTERFACE}_6 status 2>/dev/null | jsonfilter -q -l 1 -e '@.inactive.route[@.target="::"].nexthop' | tr -d "\n")
 		fi
-		#if [ "$interface_gw" != "" ] && [ "$interface_if" != "" ] && [ "$(ip -6 route show $serverip | grep $interface_if)" = "" ]; then
+		#if [ "$interface_gw" != "" ] && [ "$interface_if" != "" ] && [ -n "$serverip" ] && [ "$(ip -6 route show $serverip | grep $interface_if)" = "" ]; then
 		if [ "$interface_gw" != "" ] && [ "$interface_if" != "" ] && [ -n "$(echo $interface_gw | grep :)" ]; then
 			if [ "$multipath_config_route" = "master" ]; then
 				weight=10
@@ -469,13 +469,13 @@ set_server_route() {
 		#multipath_current_config=$(multipath $interface_if | grep "deactivated")
 		interface_current_config=$(uci -q get openmptcprouter.$OMR_TRACKER_INTERFACE.state || echo "up")
 		#if [ "$serverip" != "" ] && [ "$OMR_TRACKER_DEVICE_GATEWAY" != "" ] && [ "$(ip route show dev $OMR_TRACKER_DEVICE metric $metric | grep $serverip | grep $OMR_TRACKER_DEVICE_GATEWAY)" = "" ] && [ "$multipath_config_route" != "off" ] && [ "$multipath_current_config" = "" ]; then
-		if [ "$serverip" != "" ] && [ "$OMR_TRACKER_DEVICE_GATEWAY" != "" ] && [ "$(ip route show dev $OMR_TRACKER_DEVICE metric $metric | grep $serverip | grep $OMR_TRACKER_DEVICE_GATEWAY)" = "" ] && [ "$multipath_config_route" != "off" ] && [ "$interface_current_config" = "up" ] && [ "$interface_up" = "true" ]; then
+		if [ "$serverip" != "" ] && [ -n "$OMR_TRACKER_DEVICE" ] && [ "$OMR_TRACKER_DEVICE_GATEWAY" != "" ] && [ "$(ip route show dev $OMR_TRACKER_DEVICE metric $metric | grep $serverip | grep $OMR_TRACKER_DEVICE_GATEWAY)" = "" ] && [ "$multipath_config_route" != "off" ] && [ "$interface_current_config" = "up" ] && [ "$interface_up" = "true" ]; then
 			[ "$(uci -q get openmptcprouter.settings.debug)" = "true" ] && _log "Set server $server ($serverip) route via $OMR_TRACKER_DEVICE_GATEWAY metric $metric"
 			ip route replace $serverip via $OMR_TRACKER_DEVICE_GATEWAY dev $OMR_TRACKER_DEVICE metric $metric 2>&1 >/dev/null
 		fi
 	}
 	config_list_foreach $server ip server_route
-	if [ "$OMR_TRACKER_DEVICE_GATEWAY" != "" ] && [ "$(ip route show dev $OMR_TRACKER_DEVICE metric $metric | grep default | grep $OMR_TRACKER_DEVICE_GATEWAY)" = "" ] && [ "$multipath_config_route" != "off" ] && [ "$interface_current_config" = "up" ] && [ "$interface_up" = "true" ]; then
+	if [ -n "$metric" ] && [ "$OMR_TRACKER_DEVICE_GATEWAY" != "" ] && [ -n "$OMR_TRACKER_DEVICE" ] && [ "$(ip route show dev $OMR_TRACKER_DEVICE metric $metric | grep default | grep $OMR_TRACKER_DEVICE_GATEWAY)" = "" ] && [ "$multipath_config_route" != "off" ] && [ "$interface_current_config" = "up" ] && [ "$interface_up" = "true" ]; then
 		ip route replace default via $OMR_TRACKER_DEVICE_GATEWAY dev $OMR_TRACKER_DEVICE metric $metric 2>&1 >/dev/null
 	fi
 }
@@ -501,13 +501,13 @@ set_server_route6() {
 		#multipath_current_config=$(multipath $interface_if | grep "deactivated")
 		interface_current_config=$(uci -q get openmptcprouter.$OMR_TRACKER_INTERFACE.state || echo "up")
 		#if [ "$serverip" != "" ] && [ "$OMR_TRACKER_DEVICE_GATEWAY6" != "" ] && [ "$(ip -6 route show dev $OMR_TRACKER_DEVICE metric $metric | grep $serverip | grep $OMR_TRACKER_DEVICE_GATEWAY)" = "" ] && [ "$multipath_config_route" != "off" ] && [ "$multipath_current_config" = "" ]; then
-		if [ "$serverip" != "" ] && [ "$OMR_TRACKER_DEVICE_GATEWAY6" != "" ] && [ "$(ip -6 route show dev $OMR_TRACKER_DEVICE metric $metric | grep $serverip | grep $OMR_TRACKER_DEVICE_GATEWAY6)" = "" ] && [ "$multipath_config_route" != "off" ] && [ "$interface_current_config" = "up" ] && [ "$interface_up" = "true" ]; then
+		if [ "$serverip" != "" ] && [ "$OMR_TRACKER_DEVICE_GATEWAY6" != "" ] && [ -n "$OMR_TRACKER_DEVICE" ] && [ "$(ip -6 route show dev $OMR_TRACKER_DEVICE metric $metric | grep $serverip | grep $OMR_TRACKER_DEVICE_GATEWAY6)" = "" ] && [ "$multipath_config_route" != "off" ] && [ "$interface_current_config" = "up" ] && [ "$interface_up" = "true" ]; then
 			[ "$(uci -q get openmptcprouter.settings.debug)" = "true" ] && _log "Set server $server ($serverip) route via $OMR_TRACKER_DEVICE_GATEWAY metric $metric"
 			ip -6 route replace $serverip via $OMR_TRACKER_DEVICE_GATEWAY6 dev $OMR_TRACKER_DEVICE metric $metric 2>&1 >/dev/null
 		fi
 	}
 	config_list_foreach $server ip server_route
-	if [ "$OMR_TRACKER_DEVICE_GATEWAY6" != "" ] && [ "$(ip -6 route show dev $OMR_TRACKER_DEVICE metric $metric | grep default | grep $OMR_TRACKER_DEVICE_GATEWAY6)" = "" ] && [ "$multipath_config_route" != "off" ] && [ "$interface_current_config" = "up" ] && [ "$interface_up" = "true" ]; then
+	if [ "$OMR_TRACKER_DEVICE_GATEWAY6" != "" ] && [ -n "$OMR_TRACKER_DEVICE" ] && [ -n "$metric" ] && [ "$(ip -6 route show dev $OMR_TRACKER_DEVICE metric $metric | grep default | grep $OMR_TRACKER_DEVICE_GATEWAY6)" = "" ] && [ "$multipath_config_route" != "off" ] && [ "$interface_current_config" = "up" ] && [ "$interface_up" = "true" ]; then
 		ip -6 route replace default via $OMR_TRACKER_DEVICE_GATEWAY6 dev $OMR_TRACKER_DEVICE metric $metric 2>&1 >/dev/null
 	fi
 }
@@ -520,14 +520,14 @@ del_server_route() {
 		[ -n "$serverip" ] && _log "Delete default route via $OMR_TRACKER_DEVICE_GATEWAY dev $OMR_TRACKER_DEVICE"
 		local metric
 		metric=$(uci -q get network.$OMR_TRACKER_INTERFACE.metric)
-		[ -n "$(ip route show $serverip dev $OMR_TRACKER_DEVICE metric $metric)" ] && ip route del $serverip dev $OMR_TRACKER_DEVICE metric $metric >/dev/null 2>&1
-		[ -n "$(ip route show $serverip dev $OMR_TRACKER_DEVICE)" ] && ip route del $serverip dev $OMR_TRACKER_DEVICE >/dev/null 2>&1
-		[ -n "$(ip route show $serverip | grep $OMR_TRACKER_DEVICE)" ] && ip route del $serverip dev $OMR_TRACKER_DEVICE >/dev/null 2>&1
+		[ -n "$metric" ] && [ -n "$OMR_TRACKER_DEVICE" ] && [ -n "$serverip" ] && [ -n "$(ip route show $serverip dev $OMR_TRACKER_DEVICE metric $metric)" ] && ip route del $serverip dev $OMR_TRACKER_DEVICE metric $metric >/dev/null 2>&1
+		[ -n "$OMR_TRACKER_DEVICE" ] && [ -n "$serverip" ] && [ -n "$(ip route show $serverip dev $OMR_TRACKER_DEVICE)" ] && ip route del $serverip dev $OMR_TRACKER_DEVICE >/dev/null 2>&1
+		[ -n "$OMR_TRACKER_DEVICE" ] && [ -n "$serverip" ] && [ -n "$(ip route show $serverip | grep $OMR_TRACKER_DEVICE)" ] && ip route del $serverip dev $OMR_TRACKER_DEVICE >/dev/null 2>&1
 	}
 	config_list_foreach $server ip remove_route
-	if [ -n "$OMR_TRACKER_DEVICE_GATEWAY" ]; then
+	if [ -n "$OMR_TRACKER_DEVICE_GATEWAY" ] && [ -n "$OMR_TRACKER_DEVICE" ]; then
 		[ -n "$(ip route show default via $OMR_TRACKER_DEVICE_GATEWAY dev $OMR_TRACKER_DEVICE)" ] && ip route del default via $OMR_TRACKER_DEVICE_GATEWAY dev $OMR_TRACKER_DEVICE >/dev/null 2>&1
-	else
+	elif [ -n "$OMR_TRACKER_DEVICE" ]; then
 		[ -n "$(ip route show default dev $OMR_TRACKER_DEVICE)" ] && ip route del default dev $OMR_TRACKER_DEVICE >/dev/null 2>&1
 	fi
 }
@@ -540,13 +540,13 @@ del_server_route6() {
 		[ -n "$serverip" ] && _log "Delete default route via $OMR_TRACKER_DEVICE_GATEWAY6 dev $OMR_TRACKER_DEVICE"
 		local metric
 		metric=$(uci -q get network.$OMR_TRACKER_INTERFACE.metric)
-		[ -n "$(ip -6 route show $serverip dev $OMR_TRACKER_DEVICE metric $metric)" ] && ip -6 route del $serverip dev $OMR_TRACKER_DEVICE metric $metric >/dev/null 2>&1
-		[ -n "$(ip -6 route show $serverip dev $OMR_TRACKER_DEVICE)" ] && ip -6 route del $serverip dev $OMR_TRACKER_DEVICE >/dev/null 2>&1
+		[ -n "$OMR_TRACKER_DEVICE" ] && [ -n "$metric" ] && [ -n "$(ip -6 route show $serverip dev $OMR_TRACKER_DEVICE metric $metric)" ] && ip -6 route del $serverip dev $OMR_TRACKER_DEVICE metric $metric >/dev/null 2>&1
+		[ -n "$OMR_TRACKER_DEVICE" ] && [ -n "$metric" ] && [ -n "$(ip -6 route show $serverip dev $OMR_TRACKER_DEVICE)" ] && ip -6 route del $serverip dev $OMR_TRACKER_DEVICE >/dev/null 2>&1
 	}
 	config_list_foreach $server ip remove_route
-	if [ -n "$OMR_TRACKER_DEVICE_GATEWAY6" ]; then
+	if [ -n "$OMR_TRACKER_DEVICE_GATEWAY6" ] && [ -n "$OMR_TRACKER_DEVICE" ]; then
 		[ -n "$(ip -6 route show default via $OMR_TRACKER_DEVICE_GATEWAY6 dev $OMR_TRACKER_DEVICE)" ] && ip -6 route del default via $OMR_TRACKER_DEVICE_GATEWAY6 dev $OMR_TRACKER_DEVICE >/dev/null 2>&1
-	else
+	elif [ -n "$OMR_TRACKER_DEVICE" ]; then
 		[ -n "$(ip -6 route show default dev $OMR_TRACKER_DEVICE)" ] && ip -6 route del default dev $OMR_TRACKER_DEVICE >/dev/null 2>&1
 	fi
 }
@@ -772,12 +772,12 @@ if [ "$OMR_TRACKER_INTERFACE" = "glorytun" ] || [ "$OMR_TRACKER_INTERFACE" = "om
 		uci -q set openmptcprouter.$OMR_TRACKER_INTERFACE="interface"
 		uci -q set openmptcprouter.$OMR_TRACKER_INTERFACE.latency="$OMR_TRACKER_LATENCY"
 		if [ "$(uci -q get glorytun.vpn.enable)" != "1" ] || [ "$(uci -q get glorytun-udp.vpn.enable)" != "1" ]; then
-			if [ -n "$(uci -q get network.$OMR_TRACKER_INTERFACE.mtu)" ]; then
+			if [ -n "$(uci -q get network.$OMR_TRACKER_INTERFACE.mtu)" ] && [ -n "$OMR_TRACKER_DEVICE" ]; then
 				mtu=$(uci -q get network.$OMR_TRACKER_INTERFACE.mtu)
 				uci -q set openmptcprouter.$OMR_TRACKER_INTERFACE.mtu=$mtu
-				ip link set dev $OMR_TRACKER_DEVICE mtu $mtu > /dev/null 2>&1
+				[ -n "$mtu" ] && ip link set dev $OMR_TRACKER_DEVICE mtu $mtu > /dev/null 2>&1
 				uci -q set openmptcprouter.$OMR_TRACKER_INTERFACE.lc=$(date +"%s")
-			elif [ -z "$(uci -q get openmptcprouter.$OMR_TRACKER_INTERFACE.mtu)" ] && [ -n "$OMR_TRACKER_DEVICE_IP" ]; then
+			elif [ -z "$(uci -q get openmptcprouter.$OMR_TRACKER_INTERFACE.mtu)" ] && [ -n "$OMR_TRACKER_DEVICE_IP" ] && [ -n "$OMR_TRACKER_DEVICE" ]; then
 				if [ -n "$serverip" ] && [ "$serverip" != "127.0.0.1" ]; then 
 					local mtu=$(omr-mtu $OMR_TRACKER_DEVICE_IP $serverip)
 					#local mtu=$(omr-mtu $OMR_TRACKER_DEVICE_IP 8.8.8.8)
@@ -928,7 +928,7 @@ if [ -n "$OMR_TRACKER_DEVICE_IP" ] && [ -n "$OMR_TRACKER_DEVICE_GATEWAY" ]; then
 	elif [ "$(uci -q get openmptcprouter.settings.master)" != "failover" ]; then
 		config_foreach set_server_route server
 	fi
-	if [ "$(ip r show dev $OMR_TRACKER_DEVICE | grep default)" = "" ] && [ "$(uci -q get network.$OMR_TRACKER_INTERFACE.metric)" != "" ]; then
+	if [ -n "$OMR_TRACKER_DEVICE_GATEWAY" ] && [ -n "$OMR_TRACKER_DEVICE" ] && [ "$(ip r show dev $OMR_TRACKER_DEVICE | grep default)" = "" ] && [ "$(uci -q get network.$OMR_TRACKER_INTERFACE.metric)" != "" ]; then
 		ip r replace default via $OMR_TRACKER_DEVICE_GATEWAY dev $OMR_TRACKER_DEVICE metric $(uci -q get network.$OMR_TRACKER_INTERFACE.metric) >/dev/null 2>&1
 	fi
 fi
@@ -940,7 +940,7 @@ if [ -n "$OMR_TRACKER_DEVICE_IP6" ] && [ -n "$OMR_TRACKER_DEVICE_GATEWAY6" ]; th
 	elif [ "$(uci -q get openmptcprouter.settings.master)" != "failover" ]; then
 		config_foreach set_server_route6 server
 	fi
-	if [ "$(ip -6 r show dev $OMR_TRACKER_DEVICE | grep default)" = "" ] && [ "$(uci -q get network.$OMR_TRACKER_INTERFACE.metric)" != "" ]; then
+	if [ -n "$OMR_TRACKER_DEVICE_GATEWAY6" ] && [ -n "$OMR_TRACKER_DEVICE" ] && [ "$(ip -6 r show dev $OMR_TRACKER_DEVICE | grep default)" = "" ] && [ "$(uci -q get network.$OMR_TRACKER_INTERFACE.metric)" != "" ]; then
 		ip -6 r replace default via $OMR_TRACKER_DEVICE_GATEWAY6 dev $OMR_TRACKER_DEVICE metric $(uci -q get network.$OMR_TRACKER_INTERFACE.metric) >/dev/null 2>&1
 	fi
 fi
@@ -1080,7 +1080,7 @@ if [ "$(uci -q get openmptcprouter.$OMR_TRACKER_INTERFACE.lc)" = "" ] || [ $(($(
 					omrtracebox="$(omr-tracebox-mptcp $serverip $OMR_TRACKER_DEVICE)"
 					[ -n "$omrtracebox" ] && [ -z "$(echo $omrtracebox | grep error)" ] && uci -q set openmptcprouter.$OMR_TRACKER_INTERFACE.mptcp_status="$omrtracebox"
 				}
-				if [ "$OMR_TRACKER_INTERFACE" != "omrvpn" ] && [ "$(uci -q get glorytun.vpn.enable)" != "1" ] && [ "$(uci -q get glorytun-udp.vpn.enable)" != "1" ]; then
+				if [ "$OMR_TRACKER_INTERFACE" != "omrvpn" ] && [ "$(uci -q get glorytun.vpn.enable)" != "1" ] && [ "$(uci -q get glorytun-udp.vpn.enable)" != "1" ] && [ -n "$OMR_TRACKER_DEVICE" ]; then
 					if [ -n "$(uci -q get network.$OMR_TRACKER_INTERFACE.mtu)" ]; then
 						mtu=$(uci -q get network.$OMR_TRACKER_INTERFACE.mtu)
 						[ -n "$mtu" ] && {
@@ -1140,7 +1140,7 @@ if [ "$(uci -q get openmptcprouter.$OMR_TRACKER_INTERFACE.lc)" = "" ] || [ $(($(
 					omrtracebox="$(omr-tracebox-mptcp $serverip $OMR_TRACKER_DEVICE)"
 					[ -n "$omrtracebox" ] && [ -z "$(echo $omrtracebox | grep error)" ] && uci -q set openmptcprouter.$OMR_TRACKER_INTERFACE.mptcp_status="$omrtracebox"
 				}
-				if [ "$OMR_TRACKER_INTERFACE" != "omrvpn" ] && [ "$(uci -q get glorytun.vpn.enable)" != "1" ] && [ "$(uci -q get glorytun-udp.vpn.enable)" != "1" ]; then
+				if [ "$OMR_TRACKER_INTERFACE" != "omrvpn" ] && [ "$(uci -q get glorytun.vpn.enable)" != "1" ] && [ "$(uci -q get glorytun-udp.vpn.enable)" != "1" ] && [ -n "$OMR_TRACKER_DEVICE" ]; then
 					if [ -n "$(uci -q get network.$OMR_TRACKER_INTERFACE.mtu)" ]; then
 						mtu=$(uci -q get network.$OMR_TRACKER_INTERFACE.mtu)
 						[ -n "$mtu" ] && {