It's a dnsmasq Docker image. It is only 6 MB in size. It is just an ENTRYPOINT to the dnsmasq binary. Can you smell what the rock is cookin'?

It is usually a good idea to use a tag other than latest if you are using this image in a production setting. There are currently two tags to choose from:

• andyshinn/dnsmasq:2.72: dnsmasq 2.72 based on Alpine 3.2
• andyshinn/dnsmasq:2.75: dnsmasq 2.75 based on Alpine 3.3
• andyshinn/dnsmasq:2.76: dnsmasq 2.76 based on Alpine 3.4
• andyshinn/dnsmasq:2.78: dnsmasq 2.78 based on Alpine Edge

dnsmasq requires NET_ADMIN capabilities to run correctly. Start it with something like docker run -p 53:53/tcp -p 53:53/udp --cap-add=NET_ADMIN andyshinn/dnsmasq:2.75.

The configuration is all handled on the command line (no wrapper scripts here). The ENTRYPOINT is dnsmasq -k to keep it running in the foreground. If you wanted to send requests for an internal domain (such as Consul) you can forward the requests upstream using something like docker run -p 53:53/tcp -p 53:53/udp --cap-add=NET_ADMIN andyshinn/dnsmasq:2.75 -S /consul/10.17.0.2. This will send a request for redis.service.consul to 10.17.0.2

As this is a very barebones entrypoint with just enough to run in the foreground, there is no logging enabled by default. To send logging to stdout you can add --log-facility=- as an option.