Auto Wake On LAN script for hosts

At the very least, users should consider putting the LOGFILE on /tmp/ rather than on flash. OpenWrt also does not serve HTML pages in the same way as DD-WRT.

Note also problems with rebooting a router running this script described at https://forum.openwrt.org/t/cant-reboot-while-sleep-script-wol/

Hi guys, I found on https://www.dd-wrt.com/wiki/index.php/Useful_Scripts#Web_Server_Wake-up this useful script for wake up a host by request.
I use it to wake up my NAS if my Kodi or PC want anything from it.

Requirements:

Firmware Version: OpenWrt Barrier Breaker 14.07 / LuCI Trunk (0.12+svn-r10530)
Kernel Version: 3.10.49

Required to change	Variables	Default value	Description
optional	INTERVAL	5	repeat the script every N second
not required	OLD	empty	should be empty
optional	PORT	80	it the port who looks the script
optional	NUMP	3	the retries, before the script gave up
yes	TARGET	192.168.1.1	the wake up device
yes	INTERFACE	br-lan	here you can type in a broadcast address or a interface, i like more interface
yes	MAC	00:00:00:00:00:00	the target mac adress
not required	WOL	/usr/bin/etherwake	the program and path for wol
optional	LOGFILE	“/www/wol/index.html”	the log output folder, in this case for the url <ROUTER-IP>/wol/index.html
optional	LOGPROG	“logread”	i will read the logs from LOGREAD, but you can also read from “dmesg” or something else

Install the required packages.

opkg update
opkg install etherwake

Saving the script.

cat << "EOF" > /bin/autowol.sh
#!/bin/sh
#Enable JFFS2 and place script in /jffs/ then run on startup in web interface.
#You can check the log from http://192.168.1.1/user/wol.html
 
#debugging
#set -xv
 
INTERVAL=5
NUMP=3
OLD=""
PORT=80
TARGET=192.168.1.1
INTERFACE=br-lan
MAC=00:00:00:00:00:00
WOL=/usr/bin/etherwake
LOGFILE="/www/wol/index.html"
LOGPROG="logread" # default: dmesg
 
echo "<meta http-equiv=\"refresh\" content=\"10\">" > $LOGFILE
echo "AUTO WOL Script started at" `date` "<br>" >> $LOGFILE
 
wake_up () {
	PORT=$1
	TARGET=$2
	BROADCAST=$3
	MAC=$4
	NEW=`$LOGPROG | awk '/WOL_LOG/ && /DST='"$TARGET"'/ && /DPT='"$PORT"'/ {print }' | tail -1`
	SRC=`$LOGPROG | awk -F'[=| ]' '/WOL_LOG/ && /DST='"$TARGET"'/ && /DPT='"$PORT"'/ {print }' | tail -1`
	LINE=`$LOGPROG | awk '/WOL_LOG/ && /DST='"$TARGET"'/ && /DPT='"$PORT"'/'`
	if [ "$NEW" != "" -a "$NEW" != "$OLD" ]; then
		if ping -qc $NUMP $TARGET >/dev/null; then
			echo "NOWAKE $TARGET was accessed by $SRC and is already alive at" `date` "<br>">> $LOGFILE
		else
			echo "WAKE $SRC causes wake on lan at" `date` "<br>">> $LOGFILE
			$WOL -i $BROADCAST $MAC >> $LOGFILE
			echo "<br>" >> $LOGFILE
			sleep 5
		fi
		OLD=$NEW
	fi
}
 
while sleep $INTERVAL; do
wake_up $PORT $TARGET $INTERFACE $MAC;
done
EOF
chmod +x /bin/autowol.sh

Pro Tip: Don't copy the code above as it causes a bunch of errors due to a stray CRLF character at the end of each line. Instead just download a copy of the file here, and save yourself a day of troubleshooting!

First autostart, if the script is ok.

Go to System → Startup → Local Startup and type in:

/bin/autowol.sh

Enable debug output:

sh -x -v /bin/autowol.sh

Check the log file: http://192.168.1.1/wol/

Go to Network → Firewall → Custom Rules and add this rule:

iptables -I FORWARD 1 -p tcp -d 192.168.1.1 -m limit --limit 1/min -j LOG --log-prefix "WOL_LOG:  " --log-level 7

Auto Wake On LAN script for hosts

Script settings

Instructions

1. Preparation

2. Auto WoL script

3. Autostart

Troubleshooting