Import sensor data to RRDtool DB - bash

Question

Trying to import data to RRDtool DB for a couple of temperature sensor collected from a RFXtrx433e USB-controller. Output to .txt files
My database created like this:
[code]
# Script to create rrd-file
# 24h with 2,5 min resolution
# 7d with 5 min resolution
# 1y with 10 min resolution
# 20y with 1h resolution
directory="/home/pi/temp/rrddata/"
filename="domoticz_temp.rrd"
# Check i file already exists
if [ ! -f "$directory$filename" ]
then
# File doesn't exist, create new rrd-file
echo "Creating RRDtool DB for outside temp sensor"
rrdtool create $directory$filename \
--step 120 \
DS:probe:GAUGE:120:-50:60 \
DS:xxxx1:GAUGE:120:-50:60 \
DS:vardagsrum:GAUGE:120:-50:60 \
RRA:AVERAGE:0.5:1:576 \
RRA:AVERAGE:0.5:2:2016 \
RRA:AVERAGE:0.5:4:52560 \
RRA:AVERAGE:0.5:24:175200 \
RRA:MAX:0.5:1:5760 \
RRA:MAX:0.5:2:2016 \
RRA:MAX:0.5:4:52560 \
RRA:MAX:0.5:24:175200 \
RRA:MIN:0.5:1:5760 \
RRA:MIN:0.5:2:2016 \
RRA:MIN:0.5:4:52560 \
RRA:MIN:0.5:24:175200
echo "Done!"
else
echo $directory$filename" already exists, delete it first."
fi
Import of sensor data
rrdtool update /home/pi/temp/rrddata/domoticz_temp.rrd --template probe N:`head -n 1 </home/pi/temp/output/temp_probe.txt`
The textfile imported just contain one row with a number (temperature collected from the sensor through a LUA-script)
The code for create the graph
rrdtool graph /home/pi/temp/output/img/test/hour.png \
-w 697 -h 287 -a PNG \
--slope-mode \
--start -6h --end now \
--vertical-label "Last 6 hour temperature" \
DEF:probe=/home/pi/temp/rrddata/domoticz_temp.rrd:probe:AVERAGE \
DEF:xxxx1=/home/pi/temp/rrddata/domoticz_temp.rrd:xxxx1:AVERAGE \
DEF:vardagsrum=/home/pi/temp/rrddata/domoticz_temp.rrd:vardagsrum:AVERAGE \
COMMENT:" Location Min Max Senaste\l" \
LINE1:probe#ff0000:"Utetemp" \
LINE1:0#ff0000: \
GPRINT:probe:MIN:" %5.1lf" \
GPRINT:probe:MAX:" %5.1lf" \
GPRINT:probe:LAST:" %5.1lf\n" \
LINE1:xxxx1#00ff00:"Xxxx1" \
LINE1:0#00ff00: \
GPRINT:probe:MIN:" %5.1lf" \
GPRINT:probe:MAX:" %5.1lf" \
GPRINT:probe:LAST:" %5.1lf\n" \
LINE1:vardagsrum#0000ff:"vardagsrum" \
LINE1:0#0000ff: \
GPRINT:probe:MIN:" %5.1lf" \
GPRINT:probe:MAX:" %5.1lf" \
GPRINT:probe:LAST:" %5.1lf\n" \
Gives me this graph http://i.imgur.com/lnFxTik.png
Now to my questions:
Have I created the database and the rest of script in a correct way? I think should get NAN on the values not in the DB?
How do I import the rest of the sensors? They are in several simular TXT files.
Should/can I collect data from the sensor in another better way to get them in to the RRDtool DB?
Hope anyone can help me.
New info!
My LUA-script for collection sensor data
commandArray = {}
if (devicechanged['Probe']) then
local file = io.open("/home/pi/temp/output/temp_probe.txt", "w")
file:write(tonumber(otherdevices_temperature['Probe']))
file:close()
end
if (devicechanged['Xxxx1']) then
local file = io.open("/home/pi/temp/output/temp_xxxx1.txt", "w")
file:write(tonumber(otherdevices_temperature['Xxxx1']))
file:close()
end
if (devicechanged['Vardagsrum']) then
local file = io.open("/home/pi/temp/output/temp_vardagsrum.txt", "w")
file:write(tonumber(otherdevices_temperature['Vardagsrum']))
file:close()
end
return commandArray`

Answer 1

Yes if a value is missing you get NaN. Your create statement looks ok ... although 20y with 1h resolution ... wow!
importing from several text files would work like this
.
A=`perl -ne 'chomp;print;exit' xx1.txt`
B=`perl -ne 'chomp;print;exit' xx2.txt`
rrdtool update domoticz_temp.rrd --template xx1:xx2 N:$A:$B
.
yes instead of writing them to a file first, I would recommend to update the rrd file directly.

Answer 2

# 24h with 2,5 min resolution
# 7d with 5 min resolution
# 1y with 10 min resolution
# 20y with 1h resolution
...
rrdtool create $directory$filename \
--step 120 \
DS:probe:GAUGE:120:-50:60 \
DS:xxxx1:GAUGE:120:-50:60 \
DS:vardagsrum:GAUGE:120:-50:60 \
RRA:AVERAGE:0.5:1:576 \
RRA:AVERAGE:0.5:2:2016 \
RRA:AVERAGE:0.5:4:52560 \
RRA:AVERAGE:0.5:24:175200 \
OK, you seem to have a 2min step size, and your RRAs are consolodating 1, 2, 4 and 24 steps. This corresponds to 2min, 4min, 8min and 48min, not to 2.5, 5, 10 and 1h. Maybe your step should be 150? Also, the heartbeat on your DSs is the same as your step, which might cause you to lose data. Generally speaking, the heartbeat should be about 1.5 to 2 times the step size to allow for irregular data arrival.
However none of this relates to your 'unknown' question, much of which Tobi has already answered.
You will get 'unknown' on timeslots you have not loaded, yes.
2 and 3. Since you have a single RRD you need to have all the samples updated at the same timestamp, in the same operation. In this case, you're probably better off collecting them all at once and storing them into the same file, so that you can load them together and store into the RRD together. If this is an issue, and the sensors are probed independently, then I'd advise having a separate RRD for each sensor, so that you can update them independently. You can still generate a graph over all 3 together as you can define your graph DEFs to point to different RRD files no problem. This might be a better way to do it.
And Tobi's right about a 20y RRA possibly being somewhat excessive ;)