I am wondering if there is a chat program that works locally when the internet is out but still be connected to from the internet. I know this will be something that is self hosted.
Bonus points if I can set it up on the raspberry pi that is running Home Assistant.
Not really. You need to use a domain (correct me, if I’m wrong, but I think IP adresses don’t work) to connect to the homeserver.
In theory you could setup a DNS server in your nezwork, which resolves this domain with the local adress and then it might work, but I’m not sure if the homeserver would like that.
Also I want to add, that I use TeamSpeak, which works perfectly globally and locally, but it’s for voice chat.
Aah, yes. You’re right there. You will require a domain for it to work. Although, you could still have it work with a local DNS server for internet outages. You would still be able to chat locally in that case. But yeah, this does not seem like what OP is looking for.
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