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Turris - OpenWRT and thermometers

Turris - OpenWRT and thermometers

Posted Updated
By Petr Ruzicka
views 6 min read
Turris - OpenWRT and thermometers

Original post from linux.xvx.cz

I would like to put here some notes about the thermometers in OpenWrt and Turris.

Turris internal thermometers

Turris has its own thermometers which are monitoring the temperature of CPU and board. This how-to expects the previous lighttpd configuration described in my previous post “Turris - OpenWrt configuration”. Here is how you can create graphs from the data using RRDtool.

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mkdir -p /data/temperature_sensors /www3/temperature_sensors
#The graphs can be accessed: http://192.168.1.1/myadmin/temperature_sensors
ln -s /www3/temperature_sensors /www3/myadmin/temperature_sensors

#Create RRDtool database to store the values every 10 minutes (600 seconds) for 10 years (525600 * 600 seconds)
rrdtool create /data/temperature_sensors/temperature_sensors.rrd --step 600 \
  DS:temp0:GAUGE:1000:-273:5000 DS:temp1:GAUGE:1000:-273:5000 RRA:AVERAGE:0.5:1:525600 \
  RRA:MIN:0.5:1:525600 RRA:MAX:0.5:1:525600

#Add cron entry to put the temperatures into the database
cat >> /etc/crontabs/root << \EOF
*/10 * * * * test -f /data/temperature_sensors/temperature_sensors.rrd && rrdtool update /data/temperature_sensors/temperature_sensors.rrd $(date +\%s):$(thermometer | tr -s \\n ' ' | awk '{print $2":"$4}')
EOF

#Create main graph script
cat > /data/temperature_sensors/temperature_sensors-graph.sh << \EOF
#!/bin/sh

NAME=$(echo $0 | sed 's@.*/\([^-]*\)-.*@\1@')
RRD_FILE="/data/$NAME/$NAME.rrd"
DST_FILE="/www3/$NAME/$1.png"

RRD_PARAMETERS='
  $DST_FILE --end=$(date +%s) --vertical-label "Temperature .C" --width 1024 --height 600 --lower-limit 0
  DEF:temp0=$RRD_FILE:temp0:AVERAGE
  DEF:temp1=$RRD_FILE:temp1:AVERAGE
  LINE1:temp0#CF00FF:"10 minutes average Board\\n"
  LINE2:temp1#FF3C00:"10 minutes average CPU\\n"
  COMMENT:" \\n"
  GPRINT:temp0:MIN:"Minimum Board\\: %4.1lf .C      "
  GPRINT:temp1:MIN:"Minimum CPU\\: %4.1lf .C     "
  GPRINT:temp0:MAX:"Maximum Board\\: %4.1lf .C      "
  GPRINT:temp1:MAX:"Maximum CPU\\: %4.1lf .C\\n"
  GPRINT:temp0:AVERAGE:"Average Board\\: %4.1lf .C  "
  GPRINT:temp1:AVERAGE:"Average CPU\\: %4.1lf .C "
  GPRINT:temp0:LAST:"Current Board\\: %4.1lf .C     "
  GPRINT:temp1:LAST:"Current CPU\\: %4.1lf .C"
  > /dev/null
'

case $1 in
  daily)
    eval /usr/bin/rrdtool graph --start="end-2days" --title \'Daily graph [$(date +"%F %H:%M")]\' $RRD_PARAMETERS
  ;;
  weekly)
    eval /usr/bin/rrdtool graph --start="end-2week" --title \'Weekly graph [$(date +"%F %H:%M")]\' $RRD_PARAMETERS
  ;;
  monthly)
    eval /usr/bin/rrdtool graph --start="end-2month" --title \'Monthly graph [$(date +"%F %H:%M")]\' $RRD_PARAMETERS
  ;;
  yearly)
    eval /usr/bin/rrdtool graph --start="end-1year" --title \'Yearly graph [$(date +"%F %H:%M")]\' $RRD_PARAMETERS
  ;;
  2years)
    eval /usr/bin/rrdtool graph --start="end-2years" --title \'2 Years graph [$(date +"%F %H:%M")]\' $RRD_PARAMETERS
  ;;
  5years)
    eval /usr/bin/rrdtool graph --start="end-5years" --title \'5 Years graph [$(date +"%F %H:%M")]\' $RRD_PARAMETERS
  ;;
  10years)
    eval /usr/bin/rrdtool graph --start="end-10years" --title \'10 Years graph [$(date +"%F %H:%M")]\' $RRD_PARAMETERS
  ;;
  *)
    echo "Please specify $0 [daily|weekly|monthly|yearly|2years|5years|10years]"
  ;;
esac
EOF

chmod a+x /data/temperature_sensors/temperature_sensors-graph.sh

#Add cron entry to generate graphs
cat >> /etc/crontabs/root << EOF
7    * * * * /data/temperature_sensors/temperature_sensors-graph.sh daily
1    1 * * * /data/temperature_sensors/temperature_sensors-graph.sh weekly
2    1 * * 0 /data/temperature_sensors/temperature_sensors-graph.sh monthly
3    1 1 * * /data/temperature_sensors/temperature_sensors-graph.sh yearly
4    1 1 1 * /data/temperature_sensors/temperature_sensors-graph.sh 2years
5    1 1 1 * /data/temperature_sensors/temperature_sensors-graph.sh 5years
6    1 1 1 * /data/temperature_sensors/temperature_sensors-graph.sh 10years
EOF

You should be able to see the generated graphs in http://192.168.1.1/myadmin/temperature_sensors in the next few days.

Here is the example:

Turris temperature sensors daily graph

External thermometers

I’m using two external thermometers to monitor temperature around router + in the room. These were built according to the following descriptions:

I used the serial to USB converter and it works nicely with Digitemp:

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gate / # digitemp_DS9097 -c/etc/digitemp.conf -t0 -q -s/dev/ttyUSB0 -o"%.2C"
28.00
gate / # digitemp_DS9097 -c/etc/digitemp.conf -t1 -q -s/dev/ttyUSB0 -o"%.2C"
20.63

The scripts are very similar to the previous solution, except for getting the data from thermometers. It happens from time to time that digitemp returns bad values, so you need to read them a few times.

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mkdir -p /data/mydigitemp /www3/mydigitemp
#The graphs can be accessed: http://192.168.1.1/myadmin/mydigitemp
ln -s /www3/mydigitemp  /www3/myadmin/mydigitemp

#Create RRDtool database to store the values every 10 minutes (600 seconds) for 10 years (525600 * 600 seconds)
rrdtool create /data/mydigitemp/mydigitemp.rrd --step 600 \
DS:temp0:GAUGE:1000:-273:5000 DS:temp1:GAUGE:1000:-273:5000 RRA:AVERAGE:0.5:1:525600 \
RRA:MIN:0.5:1:525600 RRA:MAX:0.5:1:525600

#Script getting the data from thermometers
cat > /data/mydigitemp/mydigitemp.sh << \EOF
#!/bin/sh

TEMP0_ROUNDED=1000
TEMP1_ROUNDED=1000

#Sometimes the values are not in the right "range" and need to be read a few times
while [ $TEMP0_ROUNDED -gt 50 ] || [ $TEMP0_ROUNDED -lt 5 ] ; do
  TEMP0=$(/usr/bin/digitemp_DS9097 -c/etc/digitemp.conf -t0 -q -s/dev/ttyUSB0 -o"%.2C")
  TEMP0_ROUNDED=$(echo $TEMP0 | awk '{print int($1+0.5)}')
done

while [ $TEMP1_ROUNDED -gt 50 ] || [ $TEMP1_ROUNDED -lt 5 ] ; do
  TEMP1=$(/usr/bin/digitemp_DS9097 -c/etc/digitemp.conf -t1 -q -s/dev/ttyUSB0 -o"%.2C")
  TEMP1_ROUNDED=$(echo $TEMP1 | awk '{print int($1+0.5)}')
done

/usr/bin/rrdtool update /data/mydigitemp/mydigitemp.rrd $(date +%s):$TEMP0:$TEMP1
EOF

cat > /data/mydigitemp/mydigitemp-graph.sh << EOF
#!/bin/sh

RRD_FILE="/data/mydigitemp/mydigitemp.rrd"
DST_FILE="/www3/mydigitemp/$1.png"

RRD_PARAMETERS='
  $DST_FILE --end=$(date +%s) --vertical-label "Temperature .C" --width 1024 --height 600 --lower-limit 0
  DEF:temp0=$RRD_FILE:temp0:AVERAGE
  DEF:temp1=$RRD_FILE:temp1:AVERAGE
  LINE1:temp0#CF00FF:"10 minutes average inside\\n"
  LINE2:temp1#FF3C00:"10 minutes average outside\\n"
  COMMENT:" \\n"
  GPRINT:temp0:MIN:"Minimum inside\\: %4.1lf .C      "
  GPRINT:temp1:MIN:"Minimum outside\\: %4.1lf .C     "
  GPRINT:temp0:MAX:"Maximum inside\\: %4.1lf .C      "
  GPRINT:temp1:MAX:"Maximum outside\\: %4.1lf .C\\n"
  GPRINT:temp0:AVERAGE:"Average inside\\: %4.1lf .C  "
  GPRINT:temp1:AVERAGE:"Average outside\\: %4.1lf .C "
  GPRINT:temp0:LAST:"Current inside\\: %4.1lf .C     "
  GPRINT:temp1:LAST:"Current outside\\: %4.1lf .C"
  > /dev/null
'

case $1 in
  daily)
    eval /usr/bin/rrdtool graph --start="end-2days" --title \'Daily graph [$(date +"%F %H:%M")]\' $RRD_PARAMETERS
  ;;
  weekly)
    eval /usr/bin/rrdtool graph --start="end-2week" --title \'Weekly graph [$(date +"%F %H:%M")]\' $RRD_PARAMETERS
  ;;
  monthly)
    eval /usr/bin/rrdtool graph --start="end-2month" --title \'Monthly graph [$(date +"%F %H:%M")]\' $RRD_PARAMETERS
  ;;
  yearly)
    eval /usr/bin/rrdtool graph --start="end-1year" --title \'Yearly graph [$(date +"%F %H:%M")]\' $RRD_PARAMETERS
  ;;
  2years)
    eval /usr/bin/rrdtool graph --start="end-2years" --title \'2 Years graph [$(date +"%F %H:%M")]\' $RRD_PARAMETERS
  ;;
  5years)
    eval /usr/bin/rrdtool graph --start="end-5years" --title \'5 Years graph [$(date +"%F %H:%M")]\' $RRD_PARAMETERS
  ;;
  10years)
    eval /usr/bin/rrdtool graph --start="end-10years" --title \'10 Years graph [$(date +"%F %H:%M")]\' $RRD_PARAMETERS
  ;;
  *)
    echo "Please specify $0 [daily|weekly|monthly|yearly|2years|5years|10years]"
  ;;
esac
EOF

chmod a+x /data/mydigitemp/*.sh

#Add cron entries to put the temperatures into the database and create graphs
cat >> /etc/crontabs/root << \EOF
*/10 * * * * test -x /data/mydigitemp/mydigitemp.sh && /data/mydigitemp/mydigitemp.sh
0    * * * * /data/mydigitemp/mydigitemp-graph.sh daily
1    0 * * * /data/mydigitemp/mydigitemp-graph.sh weekly
2    0 * * 0 /data/mydigitemp/mydigitemp-graph.sh monthly
3    0 1 * * /data/mydigitemp/mydigitemp-graph.sh yearly
4    0 1 1 * /data/mydigitemp/mydigitemp-graph.sh 2years
5    0 1 1 * /data/mydigitemp/mydigitemp-graph.sh 5years
6    0 1 1 * /data/mydigitemp/mydigitemp-graph.sh 10years
EOF

Graph example:

External thermometers daily graph

(you can see the temperature was higher when I turned the PC near the wifi router 16:00 and 00:00)

The scripts created by the steps above can be found in GitHub.

Enjoy…

OpenWrt, linux.xvx.cz
turris monitoring
This post is licensed under CC BY 4.0 by the author.