Just a quick question. Could one of these be configured to use push, pull, type notification to operate switches and monitor senses remotely and stand alone through a remote server, much like a Sonoff type switch?. I have been trying to accomplish this through port forwarding and an IP switch but it seems I’ve hit a brick wall in that i’m behind a CGNAT and port forwarding isn’t possible. I have tried setting up No-IP as a dynamic DNS service but they said it couldn’t be done,
This is a networking issue, and not a Pi per se.
If one or both devices are behind a CGNAT implementation, the only way to connect into an open port would be to have an intermediate device sitting between them negotiating connections. For example, a VPN server that both Pis can connect into, thus creating an end-to-end VPN tunnel between them.