I can't figure out how this is functioning...
I can't figure out how this is functioning...
You're trying to set up a Minecraft server for your friends. It sounds like you've made some changes to your internet setup, but there are a few things to consider. First, having two routers might be confusing if you're not sure how they interact. Updating your regular internet connection to optical fiber helped, but if your router doesn't support it, connecting through the router is necessary. You might need to adjust your server settings or check if your friends' devices can connect via the new connection method. If you're unsure, creating a virtual server could simplify things. Let me know if you need more details!
I've set up a comparable configuration. My Sky Fibre Router struggles with WiFi performance, so I switched to a Netgear Nighthawk R8000 linked to it. All devices connect through the Nighthawk using 192.168.1.X via DHCP. To manage Sky settings, I enter 192.168.0.1 in my browser; for Netgear, 192.168.1.1 works. Port forwarding requires covering the full port range (1-65535) to the Nighthawk on the Sky router. Once set up, I can configure rules directly on the Nighthawk’s forwarding page. I verified it with a DNS test at http://dungeonseeker.ddns.net, which runs on a Raspberry Pi in my network. This external site should function without internal address issues.
I've encountered similar problems with older TP-Link devices and extenders. Whenever a TP-Link product is involved—excluding the wireless adapter—I face major issues with port-forwarding. The TP-Link VDSL2 router (W9970) lets me access ports directly, but once routed through another device like a DHCP server or bridge, all ports become inaccessible. Even adjusting port forwarding settings doesn't resolve the problem, as noted in my "Unable to Open Port 15441 on Padavan" discussion. Using a TP-Link extender (RE200, WA850RE) connected via another router has the same outcome. Switching to different brands solved it for me, though I hadn’t done that quickly after months of troubleshooting. It likely stems from firmware limitations. Now I’m using a Netgear DM200 with OpenWrt, a Xiaomi Mi 3G running PandoraBox (moving to OpenWrt soon), and a Xiaomi Mi 3 on Chinese Xwrt. Port forwarding works smoothly now.
The simplest approach is to start with the first router in bridge mode, which turns it into just a modem. If that's not feasible, configure the second router as a DMZ within the first one to handle the double NAT problem, ensuring all forwarding occurs there. Otherwise, you'll need to open the port and route it to the second router, then direct that port to the Minecraft server.