what is the easiest way to bring a switch in pimatic1 to pimatic2

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Hey there,

I have 2 instances of pimatic running on 2 different rpis. One older rpi2 at a very central position in my premises hosting a homeduino and a second one -rpi3- doing all that modern stuff (playing around, webhosting,…).
I have a few homeduino devices set up in the old pimatic. Is there an easy way to transfer the state and changes between these two? I thought about 2 solutions:
Forwarding the homeduino usb port to the new rpi with something like socat. But this may bring problems when rebooting only one of them.
Second idea was creating rules like on pimatic1 [when state changes call api of pimatic2]… but I would need to create 2 rules for every simple switch in pimatic1 (to be updated when switch is operated by remote controll) and another 2 at pimatic2 for activly using them in the front end.

Is there an easier solution?

Regards,
Anduril

Hi, I would use the machine to machine protocol (mqtt), it is designed to do so.
For example: https://forum.pimatic.org/topic/1495/sending-data-from-one-pimatic-to-another-over-mqtt

thanks @wutu, that’s an option I haven’t thought about. As I already have a running broker implementing would be easy. But is there a “mqtt switch” class that directly pub/sub its state to a given topic?
And on the old pimatic I think I have to use rules to change the homeduino switch according to the mqtt-messages and to pub it’s state on changes, right?

@anduril said in what is the easiest way to bring a switch in pimatic1 to pimatic2:

But is there a “mqtt switch” class that directly pub/sub its state to a given topic?

Yes, that’s exactly what the mqtt switch does.

And on the old pimatic I think I have to use rules to change the homeduino switch according to the mqtt-messages and to pub it’s state on changes, right?

Yes

@wutu thanks for your tips, I got 2 switches working (one on each pimatic) and acting synchronous. One question stayed in my mind: is it better to have them both listening to the same topic as they both post to (having topic and statetopic the same for all switches) or have mqttSwitchA statetopic only listening to mqttSwitchB topic and vice versa?

@anduril Hi, I would be holding simple variants. There is no reason to complicate it.

Subscribe both to the same topic and use the retain flag. That should keep them always in synch.