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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='color:#1F497D'>You’re returning the SNMP OID rssi.0<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Can you do an SNMPwalk from the command line, and retrieve this – it may be that the OID returns the value as a positive integer, or in a different form to how you expect? You may need to modify your Target line to do some sort of post-processing (for example, some devices return temperature as an integer in centidegrees Celsius, and so need to be divided by 10 (or even converted to Farenheit in certain unenlightened countries:))<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>You do not give the entire MRTG configuration stanza here for comparison, but I’ve seen it in a separate communication, so I can verify that you do not have the ‘bits’ option enabled (which would multiply by 8).<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Also, by default, MRTG assumes positive values. If using RRDTool as the backend, you need to manually tune the .rrd file to allow negative values; I think they might be rejected by native mode MRTG.<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Steve<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><div><p class=MsoNormal><b><span style='color:#1F497D'>Steve Shipway<o:p></o:p></span></b></p><p class=MsoNormal><span style='font-size:10.0pt;color:#1F497D'><a href="mailto:s.shipway@auckland.ac.nz"><span style='color:blue'>s.shipway@auckland.ac.nz</span></a><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:1.0pt;color:#1F497D'>(GNU Terry Pratchett)<o:p></o:p></span></p></div><p class=MsoNormal><span style='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 #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> mrtg [mailto:mrtg-bounces+s.shipway=auckland.ac.nz@lists.oetiker.ch] <b>On Behalf Of </b>Rick Silacci<br><b>Sent:</b> Wednesday, 6 May 2015 11:11 a.m.<br><b>To:</b> mrtg@lists.oetiker.ch<br><b>Subject:</b> [mrtg] Measuring RSSI<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span class=a><span lang=EN-US>I’m using the parameters below to measure rssi. I’m supposed to be getting a negative number expressed in decibels, but this is what I’m getting:<o:p></o:p></span></span></p><p class=MsoNormal><span class=a><span lang=EN-US><o:p> </o:p></span></span></p><p class=MsoNormal><span class=a><span lang=EN-US><o:p> </o:p></span></span></p><p class=MsoNormal><span class=a><span lang=EN-US>Variable </span></span><span class=l><span lang=EN-US>Name: RSSI</span><o:p></o:p></span></p><p class=MsoNormal><span class=a><span lang=EN-US>Variable </span></span><span class=l><span lang=EN-US>Description: Radio Signal Strength<o:p></o:p></span></span></p><p class=MsoNormal><span class=l><span lang=EN-US>Index</span></span><span class=a><span lang=EN-US style='letter-spacing:-.75pt'>SNMP/MRTG Variable </span></span><span class=a><span lang=EN-US>Name rssi.0</span><o:p></o:p></span></p><p class=MsoNormal><span class=a><span lang=EN-US>Example: Target[Var]:rssi.0&rssi.0:Canopy@MyDevice:::::2</span></span><b><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'><o:p></o:p></span></b></p><p class=MsoNormal><b><span lang=EN-US style='font-size:10.0pt;font-family:"Arial","sans-serif"'><o:p> </o:p></span></b></p><p class=MsoNormal><span class=a><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US><img border=0 width=500 height=135 id="Picture_x0020_1" src="cid:image001.png@01D087EF.84044430"><span class=a><o:p></o:p></span></span></p><p class=MsoNormal><span class=a><span lang=EN-US><o:p> </o:p></span></span></p><p class=MsoNormal><span class=a><span lang=EN-US><o:p> </o:p></span></span></p><p class=MsoNormal><span lang=EN-US style='font-size:9.0pt;font-family:"Arial Black","sans-serif"'>Rick Silacci</span><span style='font-size:9.0pt;font-family:"Arial Black","sans-serif"'><o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:9.0pt;font-family:"Arial Black","sans-serif"'>Velociter Wireless<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:9.0pt;font-family:"Arial Black","sans-serif"'>1525 Second Street<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:9.0pt;font-family:"Arial Black","sans-serif"'>Escalon, CA 95320<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:9.0pt;font-family:"Arial Black","sans-serif"'>Office: 209.838.1221<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:9.0pt;font-family:"Arial Black","sans-serif"'>Phone: 209.838.1800<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p></div></div></body></html>