[rrd-users] Fwd: Re: Aggregated Graph gives blank space when one of the interfaces does not give response

[Martin Sperl]

Hi Firdous,

I have no idea how this works with the MRTG config.
As for rrdtool itself: you would have 3 DEFS (a,b,c) and a CDEF like 
this to aggregate:
CDEF:calc=a,b,c,+,+
you will need to replace this by:
CDEF:calc=a,b,c,ADDNAN,ADDNAN

And then you will get the values even if you have a NAN for one of these 
data-sources.
(See also: http://oss.oetiker.ch/rrdtool/doc/rrdgraph_rpn.en.html for a 
description of the RPN functions)

Again: I have no idea, how to apply this to mrtg configs - someone else 
has to answer there... (possibly requires patching the mrtg graphing 
script (14all.cgi?) to use ADDNAN instead of the "+" operator.)

Ciao,
          Martin

Firdous Saleheen wrote:
> Hi Martin,
> thanks for your prompt response!
>
> the syntax I used here for aggregation is just the way I found it on mrtg-reference.
>
> the suggestion you gave would really help me if you can give a clearer idea about in which part of mrtg .cfg file or in rrdtool I have to make change. or it may be an issue of mrtg itself. then I will post the problem to mrtg site.
>
> I am a newbee in the mrtg-rrdtool arena. your help would be higly appreciated.
>
> Thanking again
>
> Firdous Saleheen
>
> From: Martin Sperl <rrdtool at martin.sperl.org>
> To: Firdous Saleheen <saleheen.firdous at mango.com.bd>
> Cc: rrd-users at lists.oetiker.ch
> Sent: Sun, 12 Apr 2009 16:23:06 +0600 (BDT)
> Subject: Re: [rrd-users] Aggregated Graph gives blank space when one of the interfaces does not give response
>
> Hi Firdous!
>
> When using rrdtool CDEFS directly: use ADDNAN instead of + in your CDEF 
> - this will ignore the NAN
> As for how this works with MRTG - no idea...
>
> Martin
>
> Firdous Saleheen wrote:
>   
>> Hi, 
>> Anyone please raise hand on the issue.
>>
>> Cheers,
>>
>> FIRDOUS SALEHEEN
>>
>>
>> -----Original Message-----
>> From: Firdous Saleheen [mailto:saleheen.firdous at mango.com.bd] 
>> Sent: Friday, April 10, 2009 3:08 PM
>> To: 'rrd-users at lists.oetiker.ch'
>> Subject: Aggregated Graph gives blank space when one of the interfaces does
>> not give response
>>
>> Hi,
>>
>> We graph our three STM-1 uplink with MRTG-RRD: singtel, tis and singtel-ctg.
>> We also graph submarine= singtel+tis+singtel-ctg writing this line in cfg
>> file :
>> Target[submarine]: 24:user at ip1:::::3 + 33:user at ip1:::::3 +
>> 17:user at ip2:::::3
>>
>>
>> It happened that there occurred a flap in our transmission line and we are
>> unable to get response from one of our devices which is connected to
>> singtel-ctg. In that instance there is a blank space in submarine graph
>> while the other two uplinks are live.
>>
>> Can anyone please point where the problem is ?
>>
>> I am attaching log here. And the version and platform are as follows:
>>
>>
>> MRTG version : 2.16.2
>> RRDtool version : 1.2.27
>> SNMP version : 3
>> Platform : CentOS release 5.2 (Final)
>>
>>
>> FIRDOUS SALEHEEN
>>
>> _______________________________________________
>> rrd-users mailing list
>> rrd-users at lists.oetiker.ch
>> https://lists.oetiker.ch/cgi-bin/listinfo/rrd-users
>>   
>>     
>
>
>