NAME

       mrtg-rrd - How to use RRDtool with MRTG

SYNOPSIS

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

        http://oss.oetiker.ch/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 following two parameters to supply the appropriate directories.

       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 previous 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 creating 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:

       One4All aka 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

       routers2.cgi
           This is another CGI frontend for 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, plus they
           support User Defined summary graphs and different levels of Authentication and Authorisation. This
           has been written by Steve Shipway (steve@steveshipway.org). You obtain a copy, and find a forum and
           demonstration system at http://www.steveshipway.org/software/ The program comes with its own
           installation instructions and install script.

       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 replacement for the 14all.cgi script. It can make
           your monitoring 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/

FUTURE

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

AUTHOR

       Tobias Oetiker <tobi@oetiker.ch>