diff --git a/luci-app-openmptcprouter/luasrc/controller/openmptcprouter.lua b/luci-app-openmptcprouter/luasrc/controller/openmptcprouter.lua
index bbb7537c3..f73b5184a 100644
--- a/luci-app-openmptcprouter/luasrc/controller/openmptcprouter.lua
+++ b/luci-app-openmptcprouter/luasrc/controller/openmptcprouter.lua
@@ -1223,11 +1223,13 @@ function set_ipv6_state(disable_ipv6)
 		luci.sys.call("uci -q del dhcp.lan.ra")
 		luci.sys.call("uci -q del dhcp.lan.ra_default")
 		luci.sys.call("uci -q del dhcp.lan.ra_management")
+		luci.sys.call("uci -q del dhcp.lan.ra_preference")
 		ucic:set("shadowsocks-libev","hi","local_address","0.0.0.0")
 	else
 		ucic:set("dhcp","lan","dhcpv6","server")
 		ucic:set("dhcp","lan","ra","server")
 		ucic:set("dhcp","lan","ra_default","1")
+		ucic:set("dhcp","lan","ra_preference","high")
 		ucic:set("dhcp","lan","ra_management","1")
 		ucic:set("shadowsocks-libev","hi","local_address","::")
 	end
diff --git a/luci-app-openmptcprouter/root/etc/init.d/openmptcprouter b/luci-app-openmptcprouter/root/etc/init.d/openmptcprouter
index 1376c44f8..adfe48c34 100755
--- a/luci-app-openmptcprouter/root/etc/init.d/openmptcprouter
+++ b/luci-app-openmptcprouter/root/etc/init.d/openmptcprouter
@@ -43,9 +43,11 @@ set_ipv6_state() {
 		uci -q delete dhcp.lan.dhcpv6
 		uci -q delete dhcp.lan.ra
 		uci -q delete dhcp.lan.ra_default
+		uci -q delete dhcp.lan.ra_preference
 		uci -q set shadowsocks-libev.hi.local_address="0.0.0.0"
 	else
 		uci -q set dhcp.lan.ra_default="1"
+		uci -q set dhcp.lan.ra_preference="high"
 		uci -q set network.lan.ipv6="1"
 		uci -q set network.lan.delegate="0"
 		uci -q set shadowsocks-libev.hi.local_address="::"