This one weird trick fixed my DNS (clickbait)

We recently got a new-internet, and with it a strange error returned I thought I fixed long ago.

I have a subdomain of inhji.de which resolves to a address in my local network. This way I can have an domain like jellyfin.nas.inhji.de with a valid certificate and have it resolve to a local address.

When I set up the new modem, I realized that the default address space is 192.168.2.0/24, whereas before it was 192.168.1.0/24. This meant I needed to setup all devices again with new ip addresses.

Nginx Proxy Manager Hosts

So I updated the Hosts on my Nginx, and thought everything would just work. And it did. But only sometimes. Sometimes the names would just not resolve.

AdGuard DNS Rewrites

So I started looking for solutions:

• I added a DNS Rewrite in my AdGuardHome, which serves as my DNS and DHCP Server
• I double-checked if my modem was not still running a DHCP server

After a few days, I suddenly remembered that it could have something to do with my tailscale network. I quickly checked the settings and found the problem.

In tailscale I had added a custom nameserver to resolve my 'local domain' with my local DNS server. That entry still had an address in my old ip range. Which made all lookups fail. No idea why it worked sometimes, but after I added the correct address of my DNS server here, the problem was solved!