Cloudflare DNS over TLS Docker container

Docker container running a DNS using Cloudflare 1.1.1.1 DNS over TLS (IPv4 only), with a built-in healthcheck and malicious websites blocking.

Download size	Image size	RAM usage	CPU usage
4.3MB	9.58MB	6MB	Very Low

It is based on:

Alpine 3.7
Unbound 1.7.0-r2
Malicious websites blacklist - a bit modified

You can also block domains of your choice, see the Extra section

Diagrams are shown for router and client-by-client configurations in the Connect clients to it section

Testing it

docker run -it --rm -p 53:53/udp qmcgaw/cloudflare-dns-server -vvv

Note the -vvv to set the verbose level to 3. It defaults to 1 if no command is provided.

See the Connect clients to it section to finish testing.

Run it as a daemon

docker run -d --name=cloudflareTlsDNS -p 53:53/udp qmcgaw/cloudflare-dns-server

You can also download and use docker-compose.yml

Connect clients to it

Option 1: Router (recommended)

All machines connected to your router will use the 1.1.1.1 encrypted DNS by default

Configure your router to use the LAN IP address of your Docker host as its primary DNS address.

Access your router page, usually at http://192.168.1.1 and login with your credentials
Change the DNS settings, which are usually located in Connection settings / Advanced / DNS server
If a secondary fallback DNS address is required, use Cloudflare address 1.1.1.1 without TLS

Option 2: Client, one by one

You have to configure each machine connected to your router to use the Docker host as their DNS server.

Docker containers

Connect other Docker containers by specifying the DNS to be 127.0.0.1

Use the argument --dns=127.0.0.1 with the docker run command
Or modify your docker-compose.yml by adding the following to your container description:
```
dns:
    - 127.0.0.1
```

Windows

Open the control panel and follow the instructions shown on the screenshots below.

Enter the IP Address of your Docker host as the Preferred DNS server (192.168.1.210 in my case) You can set the Cloudflare DNS server address 1.1.1.1 as an alternate DNS server although you might want to leave this blank so that no domain name request is in plaintext.

When closing, Windows should try to identify any potential problems. If everything is fine, you should see the following message:

Mac OS

Follow the instructions at https://support.apple.com/kb/PH25577

Linux

You probably know how to do that. Otherwise you can usually modify the first line of /etc/resolv.conf by changing the IP address of your DNS server.

Android

See this

iOS