Multi Router Traffic Grapher


The Multi Router Traffic Grapher is free software for monitoring and measuring the traffic load on network links. It allows the user to see traffic load on a network over time in graphical form.
It was originally developed by Tobias Oetiker and Dave Rand to monitor router traffic, but has developed into a tool that can create graphs and statistics for almost anything.
MRTG is written in Perl and can run on Windows, Linux, Unix, Mac OS and NetWare.

How it works

SNMP

MRTG uses the Simple Network Management Protocol to send requests with two object identifiers to a device. The device, which must be SNMP-enabled, will have a management information base to look up the OIDs specified. After collecting the information it will send back the raw data encapsulated in an SNMP protocol. MRTG records this data in a log on the client along with previously recorded data for the device. The software then creates an HTML document from the logs, containing a list of graphs detailing traffic for the selected devices in the server.

Script output

Alternatively, MRTG can be configured to run a script or command, and parse its output for counter values. The MRTG website contains a large library of external scripts to enable monitoring of SQL database statistics, firewall rules, CPU fan RPMs, or virtually any integer-value data.

Features