diff --git a/luci-app-openmptcprouter/root/etc/init.d/openmptcprouter b/luci-app-openmptcprouter/root/etc/init.d/openmptcprouter
index 647a2f36f..0518cff32 100755
--- a/luci-app-openmptcprouter/root/etc/init.d/openmptcprouter
+++ b/luci-app-openmptcprouter/root/etc/init.d/openmptcprouter
@@ -23,8 +23,10 @@ omr_intf_set() {
 
 set_ipv6_state() {
 	local disable_ipv6=$1
-	sysctl -w net.ipv6.conf.all.disable_ipv6=$disable_ipv6
-	sed -i 's:^net.ipv6.conf.all.disable_ipv6=[0-9]*:net.ipv6.conf.all.disable_ipv6=$disable_ipv6:' /etc/sysctl.d/zzz_openmptcprouter.conf
+	local sysctl_ipv6=0
+	sysctl -w net.ipv6.conf.all.disable_ipv6=$sysctl_ipv6
+	sed -i 's:^net.ipv6.conf.all.disable_ipv6=[0-9]*:net.ipv6.conf.all.disable_ipv6=$sysctl_ipv6:' /etc/sysctl.d/zzz_openmptcprouter.conf
+	
 	uci -q set firewall.@defaults[0].disable_ipv6=$disable_ipv6
 	uci -q commit firewall
 	if [ "$disable_ipv6" == "1" ]; then