OpenWRT/Lede AP: Drop FritzBox Homeplug Broadcasts

execute_on_openwrt.sh

#!/bin/sh
# Notes: AVM's FritzBox-Routers normally generate broadcast Homeplug-AV
# pakets nearly every second (used to allow for PnP-setup of these devices).
# As these pakets are responsible for a significant amount of Airtime,
# these should be blocked.
# Additionally, broadcast pakets on wifi prevent many devices from sleeping,
# and need to be transferred in legacy-rates, further bloating up the amount of wasted airtime.
# This script assumes the OpenWRT APs are 'dumb APs', whith a L2-Bridge between
# the wired and the wireless interfaces, were ebtables can block pakets based
# on their ethertype. (To check: ifconfig should only show wlan*, eth*, br-lan and lo interfaces)
opkg update 
opkg install ebtables
cat <<EOF >> /etc/firewall.user
ebtables -A FORWARD -p 88e1 -j DROP
ebtables -A FORWARD -p 8912 -j DROP
EOF
reboot

(Check whether the rules work: ebtables -L --Lc)