Is split DNS is solution for me?

Hi.

I have two problems that are (I think) connected

1. Installed nextcloud, letsencrypt, duckdns, airsonic etc. from linuxserver.io. Set up nginx reverse proxy. From my desktop, while I am on local LAN, I can perfectly browse for example: https://nextcloud.mydomain.duckdns.org/. Also, I can freely open it from my work desktop via internet. On my Android phone, while on mobile data, every domain open w/o problems, but I can not open any domain if I am at local LAN (the same LAN server is) with wi-fi connected. Any help, please?

2. Install Openvpn-as. Connect to server from my phone (mobile data only). Can browse https://nextcloud.mydomain.duckdns.org/, but can't browse 192.168.1.1 (or any site from my server which is not exposed to internet, like OMV web portal or Heimdall).

Good people on linuxserver discord suggest that I need split DNS. The problem is that I have no idea how to do that. And - my router (from internet provider) don't allow me to change DNS server. I am stuck with my provider DNSs. Any thouts, please?

Quote from jfirestorm44

I am not familiar with Nginx but I’ll give it a shot. Does your config file have localhost 127.0.01?

Also I’m not 100% sure on this but even if you used something like dnsmasq for split DNS you would need to be able to point your router at your server as the primary DNS resolver.

Have you tried pinging your domain from different devices and see which ones have a good connection. Also take note of the ip address as it should be your public one. It may also be your servers if your server is resolving.

Thank you, I will try it.