An introduction to Cacti graphs and RRDtool

In the preface, we talked about how RRDtool stores data. Now, you'll be looking into the actual graph creation process and what features Cacti supports.

Creating graphs with RRDtool

As you have seen in the preface, Cacti uses RRDtool to store the polled data. In addition to just storing the data, RRDtool is also used to create the actual performance graphs.

If you now expect to see a full-featured charting application, you will be disappointed. RRDtool graph functionality only offers a very limited range of chart types. They can either be line charts, area charts, or a combination of both. There is no 3D option available or any other type of chart, such as pie or scatter charts...