MRTG-RRD(1)                    mrtg                   MRTG-RRD(1)



NAME
       mrtg-rrd - How to use RRDtool with MRTG

SYNOPSIS
       After using MRTG for some time you may find some limita-
       tions, mostly in the areas of performance and graphing
       flexibility. These are exactly the areas addressed by RRD-
       tool. To learn more about RRDtool check out its website on

        http://people.ee.ethz.ch/~oetiker/webtools/rrdtool

RRDTOOL INTEGRATION
       When using mrtg with RRDtool you are replacing rateup with
       the RRDtool perl module RRDs.pm. To enable RRDtool support
       in mrtg you have to add the line

        LogFormat: rrdtool

       to your mrtg config file.

       MRTG needs access to both the RRDtool perl module RRDs.pm
       and to the rrdtool executable.

       If these two items are not installed in locations where
       perl can find them on its own, then you can use the fol-
       lowing two parameters to supply the appropriate directo-
       ries.

       For the location of the rrdtool executable you put

        PathAdd: /usr/local/rrdtool/bin/

       or

        PathAdd: c:\rrdtool\bin

       For the location of the perl module it would be:

        LibAdd: /usr/local/rrdtool/lib/perl/

       or

        LibAdd: c:\rrdtool\bin\lib\perl

       When you have made this modification to the configuration
       file, several things will happen when you run mrtg again
       with the new config file:

       1.  mrtg will take all your old ".log" files and convert
           them to ".rrd" format. (The ".log" files don't get
           touched in the process, so if things don't work out
           they are still there.)

       2.  mrtg will use rrdtool to update its databases. These
           will have a new format called rrd which is totally
           different than the native log format of the classic
           mrtg.

       3.  mrtg will not create any webpages of graphs anymore.
           It will only query the routers for traffic information
           and update its rrd databases.

       The advantage of whole thing is that the mrtg will become
       much faster. Expect the runtime to drop to 20% of the pre-
       vious value. (I would like to get some feedback on this
       from folks with large installations.)

       Mind you, though, while the logging process of RRDtool is
       very fast, you are also gaining some time by neither cre-
       ating graphs nor updating webpages.  The idea behind this
       is that it is more efficient to create graphs and webpages
       on demand by using a cgi script.

       At the moment there is no official script to do this, but
       two contributers have created such scripts:

       14all.cgi
           This was the first program to take over the webpage
           creation and graphing task.  It has been developed by
           Rainer Bawidamann <rainer.bawidamann@web.de>. You can
           find a copy on Rainers website:

            http://my14all.sourceforge.net/

           The program comes with its own documentation

       routers.cgi, servers.cgi and generic.cgi
           These are other cgi frontends to mrtg running with
           rrdtool. The main difference between this and 14all is
           that the web pages it creates are much more stylish
           than the ones from mrtg. These tools have been written
           by Steve Shipway <steve@steveshipway.org>. You can
           find a copy in

            http://www.steveshipway.org/software/

           The scripts comes with their own installation instruc-
           tions.

       mrtg-rrd
           The mrtg-rrd script is a CGI/FastCGI application by
           Jan "Yenya" Kasprzak for displaying MRTG graphs from
           data in the RRDtool format. It is an intended replace-
           ment for the 14all.cgi script. It can make your moni-
           toring system faster because MRTG does not have to
           generate all the PNG files with graphs every 5 minutes
           or so. Instead of this the graphs are generated on-
           demand when the user wants to see them.

              http://www.fi.muni.cz/~kas/mrtg-rrd/

       Paul C. Williamson has written a more in-depth page on how
       the whole process works, including some performance fig-
       ures. You can find his page on

          http://www.geocities.com/paulcwilliamson/mrtg/rateup2rrd.html

FUTURE
       Just as a side note: MRTG-3 will be based entirely on rrd-
       tool technology.  But don't wait for it ... get going now!

AUTHOR
       Tobias Oetiker <oetiker@ee.ethz.ch>



2.12.2                      2005-06-19                MRTG-RRD(1)
