Docker container of [dnsmasq](https://thekelleys.org.uk/dnsmasq/doc.html), an open-source DNS server. ## Usage 🐳 Via Docker Compose: ```yaml services: dnsmasq: image: dockurr/dnsmasq container_name: dnsmasq environment: DNS1: "1.0.0.1" DNS2: "1.1.1.1" ports: - 53:53/udp - 53:53/tcp cap_add: - NET_ADMIN ``` Via Docker CLI: ```bash docker run -it --rm -p 53:53/udp -p 53:53/tcp -e "DNS1=1.0.0.1" -e "DNS2=1.1.1.1" --cap-add=NET_ADMIN dockurr/dnsmasq ``` ## Configuration ⚙️ You can set the `DNS1` and `DNS2` environment variables to change which upstream DNS servers to use. In the examples above they are set to the public [Cloudflare](https://www.cloudflare.com/learning/dns/what-is-1.1.1.1/) servers. You can extend the default configuration with a volume that mounts a directory containing `*.conf` configuration files: ```yaml volumes: - /example/dnsmasq.d/:/etc/dnsmasq.d/ ``` You can also override [dnsmasq.conf](https://github.com/dockur/dnsmasq/blob/master/dnsmasq.conf) completely with a volume that binds your custom configuration file: ```yaml volumes: - /example/dnsmasq.conf:/etc/dnsmasq.conf ``` ## FAQ 💬 * ### Port 53 is already in use? If some process on the host is already binding to port `53`, you may see an error similar to the following: ``` Error response from daemon: driver failed programming external connectivity on endpoint dnsmasq (...): Error starting userland proxy: listen tcp4 0.0.0.0:53: bind: address already in use ``` You can inspect which process is binding to that port: ```bash $ netstat -lnpt | grep -E ':53 +' tcp 0 0 127.0.0.53:53 0.0.0.0:* LISTEN 197/systemd-resolve ``` On hosts running `systemd`, such as in this example, you can workaround this by specifying the IP addresses on which to bind port `53`, for example: ```yaml ports: - "192.168.1.###:53:53/udp" - "192.168.1.###:53:53/tcp" ``` There are many other host-specific cases where some process and configuration binds port `53`. It may be an unused DNS daemon, such as `bind` that needs to be uninstalled or disabled, or a number of other causes. So finding out which process is binding the port is a good place to start debugging. ## Stars 🌟 [](https://starchart.cc/dockur/dnsmasq) [build_url]: https://github.com/dockur/dnsmasq/ [hub_url]: https://hub.docker.com/r/dockurr/dnsmasq [tag_url]: https://hub.docker.com/r/dockurr/dnsmasq/tags [pkg_url]: https://github.com/dockur/dnsmasq/pkgs/container/dnsmasq [Build]: https://github.com/dockur/dnsmasq/actions/workflows/build.yml/badge.svg [Size]: https://img.shields.io/docker/image-size/dockurr/dnsmasq/latest?color=066da5&label=size [Pulls]: https://img.shields.io/docker/pulls/dockurr/dnsmasq.svg?style=flat&label=pulls&logo=docker [Version]: https://img.shields.io/docker/v/dockurr/dnsmasq/latest?arch=amd64&sort=semver&color=066da5 [Package]: https://img.shields.io/badge/dynamic/json?url=https%3A%2F%2Fipitio.github.io%2Fbackage%2Fdockur%2Fdnsmasq%2Fdnsmasq.json&query=%24.downloads&logo=github&style=flat&color=066da5&label=pulls