Connect to the host from a docker container

Use the extra_hosts option in docker-compose:

extra_hosts:
- "host.docker.internal:host-gateway"

This works in Linux but I am not sure about a Mac. Should work with the correct version of docker I think.

Make sure that this workds by pinging the host from the container e.g.

docker exec -it pine-lang_app_1 bash
ping host.docker.internal

I think the way it works is that docker understands the special string host-gateway and converts it into the actual ip to be used in order to talk to the host. Then it is upto the user to use the custom domain name i.e. host.docker.internal - so it means that there is nothing special about that domain name and it is just a convention.

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• Tags: linux docker