I’ve been having connection issues when not connected to the same network.
I’m using Duck DNS and Nginx.
I’m not sure what’s changed as it used to work, but when I’m on ANY WiFi network I can connect remotely but if I go on my phone via 4g I get the error message below. Any ideas?
I have a VPN on my phone but the app is set to bypass the VPN so it shouldn’t be that. I’m more confused as I can connect when on another person’s WiFi!!!?!?!
Your ISPs probably have blocked the DuckDNS domain, because some evil-doer have used that domain for something nasty.
Many ISPs have malware filters and some of them are not managed that well, so they just block the entire domain without looking at the usage of the domain.
The fun part is that some of the recent cases have been UK-based ISPs, like O2, and UK themself have an extra layer in the domain hierachi (.co.uk), so if international ISPs did the same, then the entire .co.uk would be blocked.
Try to connect to your URL from a browser with just http:// in front, instead of https://
My bet is that you get a page from your ISP telling you that it has blocked your connection.
It has been the duckDNS domain that have been the problem before, because that is what the ISP block on.
Best option would be getting your own domain, so noone can misuse it.
Second option would be switching to another DynamicDNS provider, but the same could then happen there. DuckDNS is just the biggest one and therefore more exposed.
VPN is by far the most secure solution and since all runs locally from HAs view, then also the simplest.
NGinX can be required for some external connection though, like Google or Alexa Assistants.