Submitted 4 weeks ago by flork@lemy.lol to selfhosted@lemmy.world
I have my home server apps configured with NGINX proxy manager and DuckDNS to access remotely, but about three weeks ago DuckDNS URLs stopped working on my home network. I can access 192.268.XXX.XXX:1234 on the home network but myapp.duckdns.org times out.
It DOES work as expected using a VPN or on mobile data.
Any ideas as to what’s going on?
Are you using your router as DNS and DHCP? With Verizon I had a security setting that was blocking public DNS entries to resolving to local addresses. I can’t remember what it’s called, but it’s to prevent a certain type of attack. For a while I disabled it but switching to pihole as DNS, DHCP and using umbound solves it without the security implications
What is your router make and model? You need to enable hairpin NAT.
Arris G36 but I don’t believe that’s the issue as it was working for years before now and on a different router too.
Could also be a stale DNS cache entry on one device or the router. If you ping your duckdns fqdn from the device that can’t connect while on your home network, does it resolve to the correct public IP?
I still think a firewall/nat issue is more likely tho.
I’ve got the same problem since a month or two with another dyndns provider. That’s not specific to the dydns provider. It is the router. Yet I have no idea how to fix it, and I am too lazy currently.
I don’t know if this will be of any help, and I dont fully understand the intricacies, but I run into similar issues with my HomeAssistant setup when the certificates expire (every couple of months?). The issue is that HA doesn’t pull the new certificate without a reboot, so I typically just restart it every once in a while to ensure that it has the newest certificate.
Thanks, but I don’t think that’s it. I rebooted and also tried adding a new container to NGINX with a DuckDNS url and it won’t load on the local network.
Did you check to be sure that DuckDNS knows your current home external IP address?
Yes and DuckDNS is working flawlessly everywhere except that the network the server is also connected to.
Sometimes DuckDNS goes down partially, their servers breaking for about a week is why I purchased a domain and now host via Cloudflare.
PerogiBoi@lemmy.ca 4 weeks ago
I had the exact same issue. My troubleshooting took me to my router. Nat Loopback and hair pinning.
Your router might have some options relating to NAT loopback or hairpinning. Apparently this can happen if your router recently had an update or if it was restarted abruptly and didn’t boot properly.
Try restarting your router. It didn’t work for me and my router is too basic for those options so in the end I took down my Nextcloud and remade another container and started from scratch. I had all sorts of things fucked with my instance so it just made sense to toss it out and fix it again.
Hope it works for you!
flork@lemy.lol 4 weeks ago
Thanks for the response but restarting the modem/router didn’t change anything, nor did creating a new container/NGINX config.