I spent days trying to find a solution to internal DNS resolution within my AdGuard DNS server and I'm happy to share that I've found one.

For context, I'm running AdGuard as my main DNS server in my home network. After pointing my Deco DHCP DNS to the AdGuard service, I was successfully seeing all the clients on my network pop up in AdGuard signifying a successful setup. However, I was frustrated by the fact that I could ONLY see the client's IP addresses and not their hostnames, or the names I assigned to them in the Deco app.

I searched everywhere and tried all sorts of settings changes in both the Deco app and AdGuard. Finally, I came across an python package that someone created for interacting with the Deco router. And that, ladies and gentlemen, is where I found success. I was able to generate a list of all connected devices and see their IP address and hostnames. From there I realized that if I could take that list and plop it into the /etc/hosts file of the AdGuard host, then AdGuard would be able to successfully resolve the client hostnames!

So that is what I did. I wrote a python script to generate an /etc/hosts file and set it on a cronjob to update every hour and now I'm happy to announce that I'm seeing hostnames for all my connected clients.

If you are also interested in doing the same, you can find my script and instructions on what I did in my GitHub repo, here: https://github.com/rusdog2784/python_utilities/blob/main/tp-link-deco/adguard-server-installation-and-setup.md

I truly hope this helps someone out there. Happy networking!