Setup: Cloudflared and Quad9

Cloudflared can be configured to use Quad9 for DNS resolution via DNS over HTTPS (DoH).

In the cloudflared.yaml configuration file, replace the Cloudflare IPs in the proxy-dns-upstream section with the Quad9 addresses associated with your desired features:

Before (Cloudflare DoH Servers)

proxy-dns-upstream:

- https://1.1.1.1/dns-query
- https://1.0.0.1/dns-query

IPv4

proxy-dns-upstream:

- https://9.9.9.9/dns-query
- https://149.112.112.112/dns-query

IPv6

proxy-dns-upstream:

- https://[2620:fe::fe]/dns-query
- https://[2620:fe::9]/dns-query