[mrtg] Configuring MRTG/rrdtool with <1 minute intervals

[Steve Shipway]

> I am currently attempting to configure MRTG/rrdtool to poll some SNMP
> statistics at a rate under 1 minute.

This is not possible using MRTG.  Check the MRTG documentation.  Although RRDTool can support intervals as low as 1 second, MRTG cannot.

> [root at snark mrtg-test]# LANG=C mrtg --check test.cfg
> Argument "0:10" isn't numeric in int
> at /usr/bin/../lib/mrtg2/MRTG_lib.pm line 100, <CFG> line 13.
> ERROR: CFG Error in "interval", line 13: 0:10 should be at least 1
> Minute and no more than 60 Minutes

This is pretty clear.  The Interval must be a numerica value, at least 1 minute and no more than 60 minutes.

> If I remove the "Interval: 0:10" line or set it to a value between 1 and
> 60 (with no seconds resolution) the configuration loads fine. What am I
> doing wrong?

You're using an interval less than 1 minute, which is not allowed.

Basically, if you want to poll data with a resolution of less than 1min, you can still use RRDTool for your backend, but you will need to create a new data collection agent and frontend to display it.

It is possible that Cricket (another RRDTool-using monitoring application) can do sub-1min intervals; I'm not sure though as I don't use it here.

Steve