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</o:shapelayout></xml><![endif]--></head><body lang=EN-NZ link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>Use <b>rrdtool info /opt/templog/data/templog.rrd</b> and check to make sure that the ‘internal’ and ‘external’ DS really do have -55 as the lowerlimit and not 0. The behaviour you describe looks like the lower limit is set to 0 (as the data seem to be absent from the RRD).<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>You may also wish to verify that you really are storing the data correctly. It is possible that the script you are using to update the RRD with the temperature data is not correctly handling negative numbers, and is not storing the data successfully.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>Steve<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>Steve Shipway<o:p></o:p></span></b></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>T: +64 9 3737 599 ext 86487<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>E: <a href="mailto:s.shipway@auckland.ac.nz">s.shipway@auckland.ac.nz</a><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:1.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>(GNU Terry Pratchett)<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><div style='border:none;border-left:solid blue 1.5pt;padding:0cm 0cm 0cm 4.0pt'><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif'>From:</span></b><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif'> rrd-users [mailto:rrd-users-bounces+s.shipway=auckland.ac.nz@lists.oetiker.ch] <b>On Behalf Of </b>s pascal<br><b>Sent:</b> Saturday, 21 November 2015 4:27 p.m.<br><b>To:</b> rrd-users@lists.oetiker.ch<br><b>Subject:</b> [FORGED] [rrd-users] graph question<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><div><div><p class=MsoNormal style='margin-bottom:12.0pt'><span style='font-family:"Verdana",sans-serif'>Hi ,<o:p></o:p></span></p></div><div><p class=MsoNormal style='margin-bottom:12.0pt'><span style='font-family:"Verdana",sans-serif'>i have this code to create the graph file<br><br><span style='color:blue'>#!/bin/sh<br>rrdtool graph /var/www/temp_graph.png \<br>-w 1024 -h 400 -a PNG --slope-mode \<br>--start -1d --end now \<br>--vertical-label "temperature (C)" \<br>DEF:out=/opt/templog/data/templog.rrd:internal:AVERAGE \<br>DEF:in=/opt/templog/data/templog.rrd:external:AVERAGE \<br>LINE2:in#00ff00:"inside" \<br>LINE2:out#000ff:"outside"</span><br><br><o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Verdana",sans-serif'>And this file to create the rrd file:<br><br><span style='color:blue'>#!/bin/sh<br>rrdtool create /opt/templog/data/templog.rrd --step 300 \<br>DS:internal:GAUGE:600:-55:125 \<br>DS:external:GAUGE:600:-55:125 \<br>RRA:AVERAGE:0.5:1:576 \<br>RRA:AVERAGE:0.5:3:1344 \<br>RRA:AVERAGE:0.5:12:1488 \<br>RRA:AVERAGE:0.5:72:1984 \<br>RRA:MIN:0.5:72:1984 \<br>RRA:MAX:0.5:72:1984</span><o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Verdana",sans-serif'><o:p> </o:p></span></p></div><div><p class=MsoNormal style='margin-bottom:12.0pt'><span style='font-family:"Verdana",sans-serif'>But when i create the graph, the temperature curve shows only positive temperature and not negative temperature.<o:p></o:p></span></p></div><div><p class=MsoNormal style='margin-bottom:12.0pt'><span style='font-family:"Verdana",sans-serif'>When the temperature is going under 0 C, the curve is blank then become visible when temperature is positive.<o:p></o:p></span></p></div><div><p class=MsoNormal style='margin-bottom:12.0pt'><span style='font-family:"Verdana",sans-serif'>How can i resolve this problem?<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Verdana",sans-serif'>Thank you<o:p></o:p></span></p></div><p class=MsoNormal><span style='font-family:"Verdana",sans-serif'>Best Regards<o:p></o:p></span></p></div></div></div></div></body></html>