RRDtool

RRDtool is a data logging and graphing application. It is based on a Round Robin Database which stores and displays time-series data. It can be used via simple shell scripts or as a perl module and is frequently used as a back-end application for other measurement tools. Like MRTG, it is flexible in what it can measure and can be used by end users to monitor trends on the end systems or by campus administrators for network information.

RRDtool was written by Tobi Oetiker based on his experiences with MRTG's log file format. RRDtool improves on that format by making it more flexible and self-describing, and by adopting a binary representation that allows for efficient updates - only a few bytes of an RRD file have to be modified for a typical update. The rrdtool command-line tool can be used to create and update RRD files, to convert them into an XML representation and back, to generate highly customizable graphs in several formats (including PNG, PDF, and SVG), and to modify the layout of an existing file.

RRDtool 2.x

In November 2012, Tobi Oetiker announced a GitHub page with some design notes on a future version of RRDtool, and asked interesting parties to join the rrd-developers@lists.oetiker.ch mailing list to discuss them.

Applications that use RRDtool

There is a huge number of applications that have adopted RRDtool to store time-series of data and to generate graphs from them. The first was probably MRTG, which supports it as an alternative to its old "native" ASCII-based format. SmokePing and Cricket are other examples.

References

• RRDtool Web page, http://oss.oetiker.ch/rrdtool/
• RRDtool 2.x - Re-Engineering RRDtool for the next 15 Years - design notes on GitHub

-- SimonLeinen - 2006-06-01 - 2012-11-01