telegraf2rrd

Config and an auxiliary program for the Telegraf (server-based agent for collecting and sending all metrics and events from databases, systems, and IoT sensors) to pass numeric data to the RRDtool database (data logging and graphing system for time series data).

Simply:

                                   [this tool]
┌─────────────┐          ┌──────────┐      ┌───────────┐        ┌──────────┐
│ IoT data,   │          │          │      │  RRDtool  │        │          │
│ system data,├─ ─ ─ ─ ─►│ telegraf ├─────►│ database  │─ ─ ─ ─►│  graphs  │
│ or other.   │          │          │      │  *.rrd    │        │          │
└─────────────┘          └──────────┘      └───────────┘        └──────────┘

each data source (e.g. mqtt topic) will be stored in the separate RRDtool database. Eg: data from /iot/home/temp topic will go to iot_home_temp.rrd etc.

How to

1. telegraf.conf

Add the following configuration to your telegraf.conf, to the section OUTPUT PLUGINS:

[[outputs.exec]]
  ## Command to ingest metrics via stdin.
  command = ["/usr/local/bin/telegraf2rrd.sh"]
  data_format = "csv"

2. The program to digest the data

Copy the telegraf2rrd.sh to your server, eg to /usr/local/bin/telegraf2rrd.sh. Remember to adjust the path in the telegraf.conf accordingly.

Variables to modify:

• topics_to_search list the topics or text strings to forward to RRD. This will be used by grep -E to search incoming messages from the telegraf.
• dbDir the directory where the rrd databases will be stored