Multiple Raspberry Pi's

Configuration
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How would Home Assistant communicate with multiple Raspberry Pi’s? I have a primary Raspberry PI that is running Home Assistant and I want to communicate with another Raspberry Pi and control a GPIO switch.

With the introduction of the Raspberry PI Zero at $5 I think this is going to become normal. I could program multiple PI Zeros for light switches/garage door openers and have Home Assistant control them.

I have successfully used HAB-node.js to get the Raspberry PI to work with Apple HomeKit/Siri and would love to know how to integrate either just the PI or HomeKit itself.

Thank you for an amazing product. I was going to try the openHAB but your interface and configuration is MUCH more polished.

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Home Assistant has support for multiple instances but it is not too stable/well tested: home-assistant.io/developers/ar … -instances

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If you want to use just one instance. You can control them over mqtt with home assistant, just like normal mqtt switch or sensor

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Could you possibly explain this a little further? I have a broker and HASS running on a Pi but I want to deploy a 2nd Pi in another location connected via LAN to exploit the GPIO. What is required on the 2nd Pi?

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Did you get anywhere with this? I’m running HomeAssistant on a Windows Server, and want to control digital signage (well, a fireplace youtube video) on a raspberry pi.

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I’ve also got some questions regarding this type of setup.

I’m running Home Assistant on a Pi 3, I’ve just picked up a Zero W and Enviro pHat

Looking at the pHat docs https://home-assistant.io/components/sensor.envirophat/ there’s no way for me to specify a hostname or IP address of this second device, and more generally what part of the question in this thread relates to is how do I target the GPIO of a Pi on the network that is not the device Home Assistant is running on?

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As suggested earlier perhaps https://home-assistant.io/developers/architecture/#multiple-connected-instances ? This is something I want to try, and I wonder if you have several slave HASS instances with identically named sensors, will the master HASS give them unique ID’s…?

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Theoretically that could be an option, though I’m hoping for a much simpler solution:

I want to be able to have many Raspberry Pi’s connected to the network with only a single instance of HASS.

Here’s what I’m thinking I’d like to do with 3 x Raspberry Pi’s ( 1 x Pi 3 & 2 x Pi Zero W)

• Pi 3 - This Pi would be in my study, indoors and running HASS

• Pi Zero W - Outside on the patio connected to a Enviro pHat

• Pi Zero W - Outside in the garage controlling my garage door via Raspberry Pi Cover

In the above scenario both the Zero’s are using the GPIO on their respective device though there are no options in either of the setups to allow me to select/target the device

I’d like to be able to do something along the lines of:

sensor:
  - platform: envirophat
    hostname: rpi-zero-one
    use_led: false
    display_options:
      - temperature
      - pressure
cover:
  - platform: rpi_gpio
    hostname: rpi-zero-two
    covers:
      - relay_pin: 10
        state_pin: 11

Where hostname: is the configuration option allowing for multiple device targets, and rpi-zero-one and rpi-zero-two are the hostnames of each of the Pi Zero’s on the network

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Agreed that would be a nice way to use HASS. Don’t believe this is possible currently, and using MQTT and custom scripts for my DIY projects

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Thanks for the kick. I was also wondering where you put the IP address and what code you run on the Pi to get them talking. I’m running HA on a VM, not a Pi so there’s nowhere to physically plug the Enviro pHAT.

Rather than install and maintain multiple instances or extend HA, it’s probably cheaper, faster, better to craft a quick Python script for the Pi that connects to the MQTT component. I’ve done this before on the Arduino platform and it works well. Your HA configuration might end up looking something like this:

- platform: mqtt
  state_topic: "sensor/1/humidity"
  name: 'f1_humidity'
  friendly_name: 'Humidity'
  unit_of_measurement: '%'

- platform: mqtt
  state_topic: "sensor/1/temperature"
  name: 'f1_temperature'
  unit_of_measurement: 'F'

- platform: mqtt
  state_topic: 'sensor/1/pressure'
  name: 'f1_pressure'
  unit_of_measurement: 'hPa'
  #value_template: '{{ value_json.pressure }}'

- platform: mqtt
  state_topic: 'sensor/1/millis'
  name: 'f1_millis'
  unit_of_measurement: 'ms'

- platform: mqtt
  state_topic: "sensor/1/rssi"
  name: 'f1_rssi'
  unit_of_measurement: 'dB'

- platform: mqtt
  state_topic: "sensor/1/battery"
  name: 'f1_battery'
  unit_of_measurement: 'V'

- platform: mqtt
  state_topic: "sensor/1/battery_level"
  name: 'f1_battery_level'
  unit_of_measurement: '%'
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Thanks @ductsoup, makes sense (I think) I’ve not yet dived into anything MQTT related yet.

That said I do want to use a few Pi Zero W’s inside the house for “room presence” detection and this also seems like a way to move forward with multiple Pi’s would be to do this with MQTT:


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Hello,

Was or is this feature planned to be implemented?

Or could anyone indicate how they are connecting with other Pi Zero W’s?

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I need to breakup my load across multiple Pis and perhaps use one for just database (InfluDB) and Grafana. has anyone leveraged multiple Pi from that approach?

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I have another way to want two pi working. I want a pi running ha in two locations and want to draw info from one to display on the other. This is in part driven by timezone differences between the two locations causing cards to get confusing on one device. But obviously resilidnce/reliability is a factor too.

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