Been around here for a year and a half, but have a question that is very basic.
If I lose internet on my router for one reason or another, should oh still be able to communicate via the network and still work properly? I would think the answer would be yes, but not sure. Should I be setting up an internal intranet?
If you lost connectivity to your Internet but there is nothing else wrong with your router, then OH will still be able to talk to everything on your LAN. So your home computers will still be able to pull up the sitemap, OH will still be able to talk to Sonoffs, etc.
It will not be able to communicate with anything outside of your home network though. So remote access through myopenhab.org will no longer work, the ability to connect to cloud-based devices (e.g. Nest) will no longer work, etc.
You can easily test this yourself. Just unplug the outgoing wire from your router, effectively cutting your router off from the Internet and explore what does and does not still work. This is probably a good experiment for everyone to run.
Was just dealing with this the last week as technicians mistakenly reallocated our phone line to someone else (thanks NBN Co).
In my personal setup most worked normally (Wemo, LIFX, Blackbean, etc) but I discovered our sensors (wirelesstag) despite being setup to work with a local IP stopped working. It killed much of the automation, as without daylight, temperature and motion detectors the home didn’t know when to act.
Thinking this sounds like a job for arduino sensors to replace the wirelesstag ones. Just have to figure how to give them decent battery life (wirelesstag ones last a year+ on a button battery) without killing their PIR etc responsiveness.