tdicola / balena-multi-device-sensor-dashboard

Demo Balena application to setup a mesh of multiple devices logging sensor data to a common TIG stack (Telegraf, InfluxDB, Grafana).

Multi-Device Sensor Logging Dashboard Demo

ROUGH DRAFT / NOTES - not final stuff!

This application demonstrates how to set up an easily extensible sensor logging dashboard with multiple devices. Telegraf, InfluxDB, and Grafana are used to collect, store, and display sensor data. To run this demo you'll need need at least one device, although any number of devices can be added to log different sensors connected to them.

Setup:

1. Create an app in Balena cloud.

2. Add devices to the application. Note that these devices must be on the same network and all able to reach a single common device which will act as the sensor data collector node.

3. Give each device a descriptive name in Balena cloud. For example collector-pi3 for a Raspberry Pi 3 that will run the data collection node, or sensor-bbb for a BeagleBone Black that is a sensor logging node.

4. Choose one device to be the collector which will host the data collection and dashboard tools (it can also log sensor data). This device should have a hostname you know set, for example use the balena CLI tools to set the hostname in the SD card boot location:

   sudo balena config write -t <device type> hostname <hostname value>
   

5. Setup environment variables used in the application. These global values will store secrets like passwords and other global configuration:

   • INFLUXDB_HOSTNAME: Set this to the hostname of the data collector node, like collector-pi3.local.
   • INFLUXDB_ADMIN_USER: This is the username of the InfluxDB admin user. Use a value of admin unless you want something else.
   • INFLUXDB_ADMIN_PASSWORD: This is the password of the InfluxDB admin user. Keep it secure and secret! (but don't worry redeploy the application to change)
   • INFLUXDB_DB: Set this to the value telegraf, it will be the name of the database created to store sensor measurements (you can change it if you want though!)
   • INFLUXDB_USER: Set this to the value telegraf, it will be the username with access to the DB created above (you can change it though, nothing is hard coded to use the value).
   • INFLUXDB_USER_PASSWORD: Set this to a secret and secure password that will be used for access to the DB.

   You can easily set them with the balena CLI tools:

   sudo balena env add -a <application name> INFLUXDB_HOSTNAME <collector hostname>
   sudo balena env add -a <application name> INFLUXDB_ADMIN_USER admin
   sudo balena env add -a <application name> INFLUXDB_ADMIN_PASSWORD secret
   sudo balena env add -a <application name> INFLUXDB_DB telegraf
   sudo balena env add -a <application name> INFLUXDB_USER telegraf
   sudo balena env add -a <application name> INFLUXDB_USER_PASSWORD secret
   

6. Edit the docker-compose.yml file and update the RUN_ON_DEVICES environment variables. Each service has one of these variables defined and it controls which device (or devices) should run the service. You'll need to set the influxdb and grafana services to run on the same device, and the sensor services to run on the appropriate devices (you can add or remove sensor services as you need too, they'll automatically log to the collector!).

7. Add any sensor data collection scripts to the telegraf service. See the comments in the docker-compose.yml which point you at the ./telegraf/collect/ folder as a location to drop shell scripts that output sensor data in InfluxDB line format.

8. Deploy the application! Push this repository to the Balena git repo.

9. If all goes well everything should be deployed and setup automatically!

10. Access your collector device on port 80 in a browser to see the grafana web interface. For the first login to the dashboard use the username admin and password admin, then it will walk you through changing the password. Note that this admin user and password is separate from the InfluxDB admin account! By default grafana will be automatically configued with a data source for the sensor data collection database under the name 'InfluxDB - Telegraf'. Create any dashboards you desire!