Collect data via modbus and input or make available to LibreNMS

Help
1

We are in the middle of R&D on a battery backup project. The charge controller we are planning on only has a Modbus connection. I have ran a LibreNMS instance in the past for a couple months and was happy with it’s capabilities. I would like to marry it together with some intermediate software so I can display and alert on the data retrieved from the modbus devices. I am happy to write that middle-ware if needed but I was just curious what LibreNMS offered for ways to get that data to it?

I see there is an API but it appears to be only for retrieving data FROM LibreNMS.

Can I work with the database directly?

Or should I rather pursue storing my data in a separate database and making it accessible via an SNMP interface so LibreNMS can poll it from there?

Any pointers here would be appreciated.

2

Hello trendal

I can see multiple ways of doing that.

  • You could use nagios plugins (https://docs.librenms.org/Extensions/Services/). They provide a variety of way to get the data from your device to LibreNMS. That seams to be the easiest solution and does not require any change in LibreNMS sourcecode.
  • You could follow the “application” way. You can look at the actual list of applications and the way they can exchange data with LibreNMS here : https://docs.librenms.org/Extensions/Applications/ .
  • You could write a proper SNMP implementation for your modbus interface to export your modbus data, and create support in LibreNMS to poll it. That variant is probably “overkill”.

Bye
PipoCanaja

3

Thanks, I’ll look into those options.

I haven’t got deep enough into LibreNMS to figure out how it works yet. It’s a bit daunting on the surface but I think if we are going to go this route I will be able to make it work.