Hello,
I have a Nextcloud server installed at home that works well on my LAN network, but when I try to make the server accessible via a DynDNS service, I cannot connect to it. The request doesn't even reach my server. My question is whether the router immediately blocks the request, because when I set the router to be accessible (it has separately that option), I can connect without any issues over dyndns url. Could my ISP (O2) be blocking it? I can confirm that it's not a firewall issue, and it's also not because I'm connected to the same WiFi as the server. It's not a port forwarding issue either, as I've gone through all possible options. My router is a Fritzbox 6660, and there are no logs indicating that a request has even come through.
My second question is whether this is even allowed in Germany? Also, I've noticed that my ISP rarely changes my IP address; in fact, I haven't seen it change at all in the past few months, which is strange because in my home country, it changed every 24 hours.
Edit: First, thank you all for your help. I will try your suggestions over the course of this week or month (due to time-related issues :) and will report back with the results. Since I am clearly a noob when it comes to self-hosting and I plan to have only a Nextcloud server for personal use, what is the best way to secure the system in these situations and allow only certain devices to access it over the external network? (if I ever manage to access it at all)
Had the same issue. I have a VM at a hoster which proxies requests to my nextcloud server at home. Both the VM and my server on my home network are connected via tailscale. I've been using the VM for other stuff as well and happened to have it anyways, I didn't get one just for this purpose
Maybe I should first ask the cellular provider for IPv6, because I misspoke; they support it but haven't enabled it for me. If they provide it, then I won't currently have a need for IPv4, but thank you for the advice.