fronius-stack

A Helm chart for installing fronius-exporter with long-term storage

Installation

helm repo add ccremer https://ccremer.github.io/charts
helm install fronius-stack ccremer/fronius-stack

⚠️ WARNING: See data retention first!

About

This Helm chart installs the fronius-exporter along with long-term storage and a Grafana dashboard. The goal is to be able to do statistics of the photovoltaic installation.

I wanted to keep fronius-exporter Helm chart minimal in case you’re only interested in the exporter or you’re bringing your own metrics stack.

Features

• fronius-exporter chart
• InfluxDB 2 chart
  • Post-Install hook to configure archival bucket with downsampling
• Grafana datasource
• Grafana dashboard

Minimal required parameters

You must configure following parameters in the minimum:

influxdb:
  adminUser:
    token: changeme
    password: changeme

fronius:
  exporter:
    symoUrl: http://your.symo.device.or.ip/solar_api/v1/GetPowerFlowRealtimeData.fcgi
  telegraf:
    influxdb:
      token: changeme # should to be the same as `influxdb.adminUser.token`!
    globalTags:
      site: my-home

Data retention

Before installing the chart, think about data retention. By default, the chart installs InfluxDB 2.0 with an initial bucket that keeps metrics for 14 days.

Additionally, the chart features a one-time post-install hook to create an archival bucket that keeps data forever. It also creates a tasks that periodically downsamples the high-precision data to 10-minute-averages into the archival bucket. This bucket is meant to hold data for years.

You can adjust retention with the following parameters:

influxdb.adminUser.retention_policy
archival.*

ℹ️ NOTE: After installation, any changes in bucket namings, retention or downsampling settings will NOT be applied anymore. You’d need to manually change this with InfluxDB CLI within the pod.

Grafana integration

The chart comes with a Grafana datasource and dashboard ConfigMaps enabled by default. Please ensure Grafana sidecar is enabled and it searches in the release namespace, or set grafana.*.namespace.

The dashboard features some panels that calculate per-day metrics. Make sure the Fronius Symo device, InfluxDB and Grafana dashboard are roughly in the same timezone. The Fronius Symo API includes counters like “energy per day” that reset at midnight.

Migrating from netdata plugin

If you have used the fronius plugin that is part of netdata, you can migrate the data to the exporter variant.

As this step is done manually once, it’s not automated, but here’s roughly how I did it:

1. Install this chart but don’t start the exporter and influxdb yet (0 replicas each). Also disable the archival feature for now.
2. Modify the InfluxDB 2.x StatefulSet, so that you can migrate using the Docker approach. You’d need to set DOCKER_INFLUXDB_INIT_MODE=upgrade and add the volume from the old DB. You can now scale the replicas to 1.
3. Once the InfluxDB 2.x is running, enter its shell and create a new fronius_archive bucket from CLI.
4. You should have now netdata/autogen, fronius_live and fronius_archive bucket. The last 2 should be empty for now.
5. Migrate & downsample the raw data from netdata/autogen bucket using the scripts provided. You might need to edit the query a bit if you are deviating from the defaults. You can execute the scripts with kubectl, e.g.

   cat migration/<the-file>.flux | kubectl -n fronius exec -i fronius-influxdb-0 -- influx query -o fronius -t $INFLUX_TOKEN
   

6. Each migration script can take a few minutes. Check the Grafana dashboard if the values make sense.
7. Scale up the exporter and verify that values are stored in fronius_live bucket.
8. Create the downsampling task for fronius_archive, check out the ConfigMap in the Helm chart that would installed on first installation.
9. Delete the netdata/autogen bucket.

Source Code

• https://github.com/ccremer/fronius-exporter

Requirements

Repository	Name	Version
https://ccremer.github.io/charts	fronius(fronius-exporter)	0.8.1
https://helm.influxdata.com	influxdb(influxdb2)	2.0.4

Values

Key	Type	Default	Description
archival.bucket	string	"fronius_archive"	Name of the archival bucket to create after installation.
archival.enabled	bool	true	Whether long-term archival is enabled. Note: Disabling archival after installation (when enabled) does not remove the archival bucket.
archival.retention	string	"0s"	Retention of the archival bucket. 0s means forever.
archival.window	string	"10m"	Fixed windows of time in which metrics are averaged.
fronius.enabled	bool	true
fronius.nameOverride	string	"exporter"
fronius.telegraf.enabled	bool	true
fronius.telegraf.globalTags.site	string	"home"	The name of the site or environment.
fronius.telegraf.influxdb.bucket	string	"fronius_live"	The high-precision bucket name, needs to be equal to influxdb.adminUser.bucket.
fronius.telegraf.influxdb.token	string	""	The token to connect to InfluxDB, needs to be equal to influxdb.adminUser.token.
fronius.telegraf.influxdb.url	string	"http://fronius-influxdb"
fronius.telegraf.interval	string	"5s"	Interval of sending metrics to InfluxDB.
fullnameOverride	string	""
grafana.dashboard.enabled	bool	true
grafana.dashboard.labels	object	{"grafana_dashboard":"1"}	The labels which the sidecar is filtering for dashboards.
grafana.dashboard.namespace	string	""	Override the namespace where the ConfigMap is installed, defaults to release namespace.
grafana.datasource.enabled	bool	true
grafana.datasource.labels	object	{"grafana_datasource":"1"}	The labels which the sidecar is filtering for data sources.
grafana.datasource.namespace	string	""	Override the namespace where the ConfigMap is installed, defaults to release namespace.
influxdb.adminUser.bucket	string	"fronius_live"
influxdb.adminUser.organization	string	"fronius"
influxdb.adminUser.retention_policy	string	"14d"
influxdb.enabled	bool	true
influxdb.pdb.create	bool	false
influxdb.persistence.size	string	"2Gi"
influxdb.resources.limits.memory	string	"256Mi"
influxdb.resources.requests.cpu	string	"50m"
influxdb.resources.requests.memory	string	"128Mi"
nameOverride	string	"fronius"