Remote access

[TheDreadPirate]

SUA is the correct mode for NAT.

From the info you provided, your port forwarding and Cloudflare setup are correctly. The only thing that would prevent it from working is if your ISP uses CGNAT (carrier grade NAT). Similar to how consume level NAT works, 1 public IP for multiple devices, some ISPs do the same at the ISP level. CGNAT pretty much makes it impossible to host a service since your IP changes pretty frequently and the carrier blocks unsolicited incoming requests like your router would if you don't setup port forwarding.

If you go to https://whatismyipaddress.com/ again and if the IP is different than yesterday, that is a pretty good indicator that your USP uses CGNAT.

DNS route is definitely not it, based on the description.

In LAN Options, can you show me "IP Alias"?

Or you can provide me with your router model and maybe I can find a manual for that model.