No, you have 1 packet loss.  It is recorded as:

1366720500: -nan 9,3666666667e-01 
1366720800: -nan 6,3333333333e-02 

That is, 0.937 of a packet and, 5 minutes later, 0.033 of a packet.  That is why
maximum packet loss is 0.937/20 = 4.68% instead of 5%

It does this because the packet loss measurement occurred at roughly 1366720520 
and the
measurement is interpolated.  Actually I think it is a little more complicated
that that, but that is the basic concept.  This Works great when you are not 
worried about perfect precision, but not so great when you are trying to 
measure integers!


-Russell Dwarshuis

----- Original Message -----
From: "Alessandro Palermo" <[email protected]>
To: "Russell Dwarshuis" <[email protected]>
Cc: "smokeping-users" <[email protected]>
Sent: Tuesday, April 23, 2013 1:58:56 PM
Subject: Re: [smokeping-users] Get packet loss data in last ten days graph


I still got a doubt about the calculataion of packet loss. 
For example I've got 2 losses in the last 3 hours in two consecutives polling 
cycles (1/20 and 1/20). 
The data in the graphs shows pl= 0.14% avg and 4.68% max 
In the rrd data I've got: 

rrdtool fetch myrrdfile.rrd AVERAGE -s -3h -e now | cut -f 1-3 -d' ' 


1366717200: -nan 0,0000000000e+00 
1366717500: -nan 0,0000000000e+00 
1366717800: -nan 0,0000000000e+00 
1366718100: -nan 0,0000000000e+00 
1366718400: -nan 0,0000000000e+00 
1366718700: -nan 0,0000000000e+00 
1366719000: -nan 0,0000000000e+00 
1366719300: -nan 0,0000000000e+00 
1366719600: -nan 0,0000000000e+00 
1366719900: -nan 0,0000000000e+00 
1366720200: -nan 0,0000000000e+00 
1366720500: -nan 9,3666666667e-01 
1366720800: -nan 6,3333333333e-02 
1366721100: -nan 0,0000000000e+00 
1366721400: -nan 0,0000000000e+00 
1366721700: -nan 0,0000000000e+00 
1366722000: -nan 0,0000000000e+00 
1366722300: -nan 0,0000000000e+00 
1366722600: -nan 0,0000000000e+00 
1366722900: -nan 0,0000000000e+00 
1366723200: -nan 0,0000000000e+00 
1366723500: -nan 0,0000000000e+00 
1366723800: -nan 0,0000000000e+00 
1366724100: -nan 0,0000000000e+00 
1366724400: -nan 0,0000000000e+00 
1366724700: -nan 0,0000000000e+00 
1366725000: -nan 0,0000000000e+00 
1366725300: -nan 0,0000000000e+00 
1366725600: -nan 0,0000000000e+00 
1366725900: -nan 0,0000000000e+00 
1366726200: -nan 0,0000000000e+00 
1366726500: -nan 0,0000000000e+00 
1366726800: -nan 0,0000000000e+00 
1366727100: -nan 0,0000000000e+00 
1366727400: -nan 0,0000000000e+00 
1366727700: -nan 0,0000000000e+00 
1366728000: -nan -nan 

And I can't understand how to obtain the value of pl=0.14% avg. I thought that 
the data stored in the rrd was the number of packet loss in a round or the 
average each 5 minutes. 
In the first case I get a value of pl=(number of packet losses in last 
3hours/total packets sends)2/720=0.0028, then pl=0.28%. 
Surely I'm wrong in something. 

Thanks 




On 22 April 2013 21:32, Alessandro Palermo < [email protected] > wrote: 




Thanks very much Russell. I will try this. 

Regards 
El 22/04/2013 15:36, "Russell Dwarshuis" < [email protected] > escribió: 




Here is an example (I piped it through cut so you don't have to see all 20 ping 
times): 
rrdtool fetch your.rrd AVERAGE -s -20minutes -e now | cut -f 1-3 -d' ' 


1366654200: nan 0.0000000000e+00 5.7700000000e-03 5.7600000000e-03 
1366654500: nan 0.0000000000e+00 5.7700000000e-03 5.7600000000e-03 
1366654800: nan 0.0000000000e+00 5.7700000000e-03 5.7600000000e-03 
1366655100: nan 0.0000000000e+00 5.7714666667e-03 5.7600000000e-03 

Loss is in column 3 (0.0000000000e+00) 



-Russell Dwarshuis 

----- Original Message ----- 
From: "Alessandro Palermo" < [email protected] > 
To: [email protected] 
Sent: Monday, April 22, 2013 10:42:46 AM 
Subject: [smokeping-users] Get packet loss data in last ten days graph 





Hi list. 
I'm monitoring around 300 wan links with fping probe with no problem. I have 
tuned smokeping to get more information I have added a plugin to show the lasts 
median rtt in a gauges view and a link to show the information about the route 
of each wan links and record the changes in the routes. 
Now I want to create a report to monitoring the packet loss in the last ten day 
and send a mail with the graph of the links that have a packet loss greater 
than 5% per example. 
How can i get this value for the .rrd files? I've been inspected the rrd files 
but I just see the last loss value. 

Thanks in advance 

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