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<P><FONT SIZE=2 FACE="Arial">I have received a question from our network management group concerning how the packet loss is calculated by Smokeping.</FONT>
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<P><FONT SIZE=2 FACE="Arial">I have tried to understand this and failed miserably.</FONT>
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<P><FONT SIZE=2 FACE="Arial">For example, here is a record from one of my rrd files:</FONT>
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<P><FONT SIZE=2 FACE="Arial">1170982800: NaN 5.3841740667e+00 3.5863971281e-02 3.4867749856e-02 3.4867749856e-02 3.4867749856e-02 3.4867749856e-02 3.5863971281e-02 3.5863971281e-02 3.5863971281e-02 3.5863971281e-02 3.5863971281e-02 3.9848856978e-02</FONT></P>
<P><FONT SIZE=2 FACE="Arial">Loss 5.3841740667e+00 </FONT>
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<P><FONT SIZE=2 FACE="Arial">Ping Median 00 3.5863971281e-02 </FONT>
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<P><FONT SIZE=2 FACE="Arial">Ping 1 3.4867749856e-02 </FONT>
<BR><FONT SIZE=2 FACE="Arial">Ping 2 3.4867749856e-02 </FONT>
<BR><FONT SIZE=2 FACE="Arial">Ping 3 3.4867749856e-02</FONT>
<BR><FONT SIZE=2 FACE="Arial">Ping 4 3.4867749856e-02</FONT>
<BR><FONT SIZE=2 FACE="Arial">Ping 5 3.5863971281e-02</FONT>
<BR><FONT SIZE=2 FACE="Arial">Ping 6 3.5863971281e-02</FONT>
<BR><FONT SIZE=2 FACE="Arial">Ping 7 3.5863971281e-02</FONT>
<BR><FONT SIZE=2 FACE="Arial">Ping 8 3.5863971281e-02</FONT>
<BR><FONT SIZE=2 FACE="Arial">Ping 9 3.5863971281e-02</FONT>
<BR><FONT SIZE=2 FACE="Arial">Ping 10 3.9848856978e-02</FONT>
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<P><FONT SIZE=2 FACE="Arial">Several questions: </FONT>
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<P><FONT SIZE=2 FACE="Arial">Where did the 5.3841740667e+00 for packet loss come from? How was it calculated? </FONT>
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<P><FONT SIZE=2 FACE="Arial">Does the percentage reflecting in that calculation only come from this specific RRD record? </FONT>
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<P><FONT SIZE=2 FACE="Arial">How can a loss calculation base on 10 pings not return a loss percentage that is 10%, 20% 30%, etc?</FONT>
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<P><FONT SIZE=2 FACE="Arial">Or does it somehow span multiple records? All 10 fields in the record show values, although many are exactly the same, which is highly unlikely. I only see 3 unique values, which tells me that the packet loss was more like 70% (three good response time numbers and Smokeping likely just kept the previous value for the packets that were lost)? </FONT></P>
<P><FONT SIZE=2 FACE="Arial">Help on these questions would be highly appreciated.</FONT>
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<P><FONT SIZE=2 FACE="Arial">Vern </FONT>
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