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: