Possible to sum rrd into one graph ?

If you're using DEFs like this:

      [la]
           TITLE CPU Load
           YAXIS Load
           DEF:avg=la.rrd:la:AVERAGE
           CDEF:la=avg,100,/

you can definitely use a pathname for the RRD.  I do exactly that with some
performance graphs where I can't use xymon:

     DEF:server1avg=/var/lib/perfmon/server1/loadavg.rrd
     DEF:server2avg=/var/lib/perfmon/server2/loadavg.rrd

I don't know if the same is true of the FNPATTERN style of setting DEFs.

Of course, if your RRD are on different physical machines, that's a bit
harder...  :)

Ralph Mitchell


On Fri, Aug 27, 2010 at 7:34 AM, SEGLARD, Thomas <user-befbea81d840@xymon.invalid> wrote:

 Hello,


yes, you’re right.


But, my mistake, this is only part of answer and I don’t exactly write what
I wanted to know. What I want is a way to sum the RRDs from different
servers and corresponding to the graph definition « ifstat ». The main
problem is that the RRDs are not in the same place/directory and thus I have
no way to tell rrdtool where to get these RRDs. This is the main problem and
why I required some help J


I could do some scrtipt which sync on a regular basis these RRDs into one
server directory. It’s not very elegant (but I think this will work !). In a
future release, maybe it will be possible to use the Metrics reports to do
all the maths we want with different RRDs ? ;)


Nobody uses Xymon to graph the sum of network bandwidth from different
sources (firewall, lb, media servers, web servers, etc…) into one graph ??


Sincerly,


Thomas


*De :* Ralph Mitchell [mailto:user-00a5e44c48c0@xymon.invalid]
*Envoyé :* vendredi 27 août 2010 13:04

*À :* xymon at xymon.com
*Objet :* Re: [xymon] Possible to sum rrd into one graph ?


Take a look at the man page for rrdgraph_data.  That describes how to use
CDEF:


     CDEF

         CDEF:vname=RPN expression


         This command creates a new set of data points (in memory only, not
in

         the RRD file) out of one or more other data series.


After using DEF to define the variables being pulled from the various RRDs,
you should be able to combine them with a math expression.  You would then
use the CDEF vname in the graph LINE, AREA, etc.


Ralph Mitchell

On Fri, Aug 27, 2010 at 3:56 AM, SEGLARD, Thomas <user-befbea81d840@xymon.invalid> wrote:

Hi Josh,


First, thank you for this link. Second, I’m sorry but I don’t understand
very well your example. I don’t want to graph multiple RRD sources, I want
to graph the sum of multiple RRD sources J Do you think Xymon could make
it ?


Thanks for help.


Thomas


*De :* Josh Luthman [mailto:user-4c45a83f15cb@xymon.invalid]
*Envoyé :* jeudi 26 août 2010 17:20


*À :* xymon at xymon.com
*Objet :* Re: [xymon] Possible to sum rrd into one graph ?


https://sourceforge.net/apps/mediawiki/xymon/index.php?title=Graph_multiple_RRD_sources

On Aug 26, 2010 8:04 AM, "SEGLARD, Thomas" <user-befbea81d840@xymon.invalid> wrote:

Hello,


In Munin, its possible to sum several rrd into one graph (ie : to display
the total bandwidth used by all your media servers). Thus, I’m asking if
it’s possible to do this in XYmon too ? I saw the « Metrics reports » but
you can’t sum graphs…

Regards,


Thomas SEGLARD