diff --git a/defaults/rc.conf b/defaults/rc.conf
index 016ee24..e1ff014 100644
--- a/defaults/rc.conf
+++ b/defaults/rc.conf
@@ -21,6 +21,8 @@
 
 rc_router_debug="NO"
 
+build_sysctl_enable="YES"
+
 generate_internal_dhcpv4_enable='YES'
 generate_isp_dhcp_enable='YES'
 generate_rtadvd_conf_enable="YES"