Sudden DNS issue (possibly Quad9) on B One

General
1

I’ve been using a B One for over a year, and have had a stable configuration for months without issue.

One day last week, out of the blue, all clients started experiencing delayed DNS resolution. My configuration has the following settings:

  • The single active WAN has assigned DNS addresses (Cloudflare and Quad9)
  • The WLAN and LAN clients have the B One as the DNS source
  • DNS Caching enabled
  • DNS over HTTPS enabled (via Quad9)
  • In Service Forwarding, Forward Outgoing DNS Requests to Local DNS Proxy is enabled

After a great many experiments, including updating firmware to 8.5.2, I discovered that the only way to eliminate the timeouts was to either cut the B One out of the DNS loop (manually assigning DNS servers to clients plus disabling the forwarding of DNS requests), or by simply switching away from Quad9 in the DNS over HTTPS setting.

Anyone else experiencing something like this? Thanks!

2

Have you disabled the DNS proxy on the B One? it is enabled by default.

3

If you’re referring to the DNS Proxy in the Service Forwarding section, then yes, I played around with it. Is there another setting I overlooked?

With Quad9 as the DNS-over-HTTPS setting, if I enabled that DNS proxy but left the B One as the assigned DNS source for clients then I still get timeouts. I had to also have DHCP assign explicit external DNS servers to avoid the timeouts under these circumstances.

Whereas if I instead simply switched from Quad9 to Cloudflare as the DNS-over-HTTPS destination, the timeouts disappeared.