GL.iNet's AdGuard Home Hides Upstream DNS Settings in a Non-Obvious Place

me@ssoriche.com (Shawn Sorichetti) — Tue, 03 Mar 2026 00:00:00 +0000

On a recent trip I kept getting connection failures that needed retrying — pages half-loading, API calls timing out, the usual DNS-smells-wrong experience. It was intermittent enough to be annoying but consistent enough that I knew something was actually broken.

I narrowed it down to DNS pretty quickly. My GL.iNet MT-3000 travel router was dropping queries or returning nothing for some domains.

The culprit turned out to be obvious in retrospect: before leaving I had shut down my Pi-hole servers at home. Those Pi-holes live on my Tailscale network, and my travel router connects back to that network. Somewhere, something was still trying to use them for DNS.

Pihole on Shawn Sorichetti

GL.iNet's AdGuard Home Hides Upstream DNS Settings in a Non-Obvious Place