Running OpenHAB on several Raspberry Pis

I am hoping to use OpenHAB to control the heating in my home. I currently have some Bluetooth LE radiator valve actuators (I have three types, Comet Blue, EQ3 and Xavax). I am going to need several Bluetooth masters to cover the whole house. Can I run OpenHAB on several Raspberry Pi Zero W’s, and have them all cooperate in some way? Obviously I only want to have one web site to use to control the system. Or can I run some other sort of software on all but one of the RaspPis so that it just accesses the radiator valves near it, and then communicates this (presumably via WiFi) with the master that’s running OpenHAB? What is the best way to set this up so that it works?

Thanks - Rowan

First of all, it is not recommended to run OH on a Pi Zero.
For multiple Pis I think you should use MQTT to communicate back to your central system.

No and yes. As Bruce indicates, you can’t really run OH on an RPi 0. There isn’t enough RAM. But yes, you can run multiple OH instances and federate them using the MQTT 2.5 Event Bus.

However, that probably isn’t the best way to accomplish this, especially given that OH doesn’t have good support for BT devices. The Bluetooth binding pretty much only supports a couple of beacons. So OH is probably not going to be your best choice for controlling the actuators. You will likely need to find a Python script or something like that on github to actually control them.

Then with that in hand and working you can set up communication between them and a single OH, MQTT is a popular choice. You can almost certainly run such a Python script on an RPi 0 without problem.

Your big task is going to be finding something written to interact with and control your specific devices. Once you have that the best over all approach may become more apparent.

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I’ve had a similar problem. I’ve got OH running on a pi and also need to talk to the electric blinds around the house. Bluez, the underlying driver on rpi, is not good being used in a server environment with ble and low rssi. It crashes and hangs which then leaves your process stuck until you code around it. The pi zeroW is far worse than a normal pi too

Your pi running OH is your server, keep it like that. Offload all the “interactive” stuff to other devices.
I’ve ended up with two pi-zeroW up stairs and two downstairs which give good enough coverage for now.