diff --git a/mptcp/files/etc/init.d/mptcp b/mptcp/files/etc/init.d/mptcp
index 99cd7d0db..375c60276 100755
--- a/mptcp/files/etc/init.d/mptcp
+++ b/mptcp/files/etc/init.d/mptcp
@@ -295,8 +295,8 @@ interface_multipath_settings() {
 		config_get gateway6 $config ip6gw
 		if [ -n "$ipaddr6" ]; then
 			ip6addr=`echo $ip6addr | cut -d/ -f1`
-			netmask6=`ipcalc $ipaddr6 | sed -n '/PREFIX=/{;s/.*=//;s/ .*//;p;}'`
-			network6=`ipcalc $ip6addr | sed -n '/NETWORK=/{;s/.*=//;s/ .*//;p;}'`
+			netmask6=`ipcalc -p $ipaddr6 | sed -n '/PREFIX=/{;s/.*=//;s/ .*//;p;}'`
+			network6=`ipcalc -n $ip6addr | sed -n '/NETWORK=/{;s/.*=//;s/ .*//;p;}'`
 		fi
 		if [ -z "$ip6addr" ] || [ -z "$network6" ]; then
 			[ -z "$ip6addr" ] && network_get_ipaddr6 ip6addr $config
@@ -312,7 +312,7 @@ interface_multipath_settings() {
 				gateway6=$(ubus call network.interface.${config}_6 status 2>/dev/null | jsonfilter -q -l 1 -e '@.inactive.route[@.target="::"].nexthop' | tr -d "\n")
 			fi
 			netmask6=$(ip -6 addr show dev $iface | grep -v 'scope link' | grep inet6 | awk '{print $2}' | cut -d/ -f2 | tr -d "\n")
-			[ -n "$ip6addr" ] && network6=`ipcalc $ip6addr | sed -n '/NETWORK=/{;s/.*=//;s/ .*//;p;}'`
+			[ -n "$ip6addr" ] && network6=`ipcalc -n $ip6addr | sed -n '/NETWORK=/{;s/.*=//;s/ .*//;p;}'`
 		fi
 		if [ "$(uci -q get openmptcprouter.settings.uci_route)" = "1" ]; then
 			uci -q batch <<-EOF >/dev/null