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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'>It looks like the OID is returning a string value. MRTG expects a Counter, so this is not going to work without postprocessing using the ConversionCode directive and Target suffixes.<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 need to define a Conversion function, like this.<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'>First, create a file conversion.pl in the same directory as the mrtg script containing this:<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span style='font-family:"Courier New"'>sub string2int {<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Courier New"'> my $value = shift;<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Courier New"'> if ( $value =~ /(-?\d+\.?\d*)/ ) { return $1; } else { return undef; }<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Courier New"'>}<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'>In your MRTG cfg file, have this to declare the functions:<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal style='text-indent:36.0pt'><b><span style='font-family:"Courier New";color:#1F497D'>ConversionCode: conversion.pl<o:p></o:p></span></b></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Then, in your Target line, use something like this to use </span><span style='font-family:"Courier New";color:#1F497D'>string2int</span><span style='color:#1F497D'> to postprocess the output:<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal style='text-indent:36.0pt'><span style='font-family:"Courier New"'>Target[ezwf]: rssi.0&rssi.0:community@devicename:::::2<b>|string2int</b><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'>This will extract the ‘-77’ from the string “-77 dBm”.<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'>However, if you are using native MRTG, you ‘ll have problems with decimals and negative numbers as they are not supported. To get around this, you could use a simple regexp in the </span><span style='font-family:"Courier New";color:#1F497D'>string2int</span><span style='color:#1F497D'> function, such as </span><span style='font-family:"Courier New";color:#1F497D'>/(\d+)/</span><span style='color:#1F497D'> which will ignore and decimals and negatives.<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 could use<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal style='text-indent:36.0pt'><span style='font-family:"Courier New"'>Factor[ezwf]: -1<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'>…to display the (positive) stored values as negative, though I’m not certain if native-mode MRTG supports negative Factor[] definitions either. Have another recommendation to use the RRDTool backend </span><span style='font-family:Wingdings;color:#1F497D'>J</span><span style='color:#1F497D'> - maybe you can convince your management…<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"'> Rick Silacci [mailto:rick@velociter.net] <br><b>Sent:</b> Thursday, 7 May 2015 5:09 a.m.<br><b>To:</b> Steve Shipway<br><b>Subject:</b> RE: Measuring RSSI<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><b><span lang=EN-US style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#1F497D'>Actually I walked the correct OID </span></b><b><span lang=EN-US style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#2F5597'>1.3.6.1.4.1.161.19.3.2.2.8.0 and it came back with “-77 dBm” When I poll it through mrtg I get error message: Warning: Expected a number but got –‘77 dBm’<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";color:#2F5597'><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";color:#2F5597'><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";color:#2F5597'>I need to suppress the ‘dbm’ part. Is that possible?<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";color:#1F497D'><o:p> </o:p></span></b></p><div style='border:none;border-left:solid blue 1.5pt;padding:0cm 0cm 0cm 4.0pt'><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p></div></div></div></body></html>