#!/bin/sh

# copy script to rootfs to avoid preventing the disks from spinning down
cp /ffp/bin/fan_ctrl_cron.sh /usr/bin/

# add the fan control script to the current cron list at 1 minute intervals
echo "$(crontab -l;echo '*/1 * * * * /usr/bin/fan_ctrl_cron.sh')"|crontab -

#!/bin/sh

#
# Script to control the fan speed on a D-Link DNS-323
#
# Note: This script is intended to be ran from the cron
#
# Author: Bruno Gravato
#
# version: 1.0
#

PATH=/usr/bin:/bin:/usr/sbin:/sbin

# kill original fancontrol daemon
PID=`pidof fancontrol`
if [ "$PID" != "" ]
then
kill -9 $PID
fi

# variables (temperatures are in Fahrenheit)
#
# fan will stop when temperature reaches this value
TEMP_STOP=99
# fan will spin at low speed when temperature reaches this value
TEMP_LOW=105
# fan will spin at high speed when temperature reaches this value
TEMP_HIGH=113
# this is fan's rpm (rotations per minute) reference point to determine
# wether the fan is rotating at high or low speed
RPM_REF=4000

# get current temperature and fan speed
TEMP=$(temperature g 0)
TEMP=${TEMP##*=}
SPEED=$(fanspeed g)

# check fan speed
if [ $SPEED -lt 1 ]
# fan is stopped
then
if [ $TEMP -ge $TEMP_HIGH ]
then
# set high speed
fanspeed h
elif [ $TEMP -ge $TEMP_LOW ]
then
# set low speed
fanspeed l
fi
else
# fan is spinning
if [ $TEMP -le $TEMP_STOP ]
then
# stop the fan
fanspeed s
elif [ $SPEED -lt $RPM_REF ]
# fan at low speed
then
if [ $TEMP -ge $TEMP_HIGH ]
then
# set high speed
fanspeed h
fi
else
# fan at high speed
if [ $TEMP -le $TEMP_LOW ]
then
# set low speed
fanspeed l
fi
fi
fi