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A good ressource for what is needed for this three containers is https://www.eydam-prototyping.com/2021/01/09/smart-home-zentrale-mit-dem-raspberry-pi/. If you are thinking about backing up the Docker volums, give "duplicati" a try: https://www.himpler.com/blog/smart-home-setup-mit-docker/
In my installations the "/srv" directory is ised to place the configurations.
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