Docker: get host ip from container

Host IP

To get the host’s IP from a container:

  • in MacOS and Windows, just use the host: host.docker.internal. If you ping this host, you will be able to see the host ip.
  • in Linux, inside container, run /sbin/ip route|awk '/default/ { print $3 }' and usually this print ip: 172.17.0.1

docker-compose file

So in your docker-compose.yml file, if you want to connect to your host’s redis:

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services:
    app:
        environment:
            REDIS_SERVER: ${DOCKER_HOST:-host.docker.internal}:6379

The REDIS_SERVER env var indicates that if the env var DOCKER_HOST exists, if it exists, use that value, otherwise, use string host.docker.internal .

So in Linux before we do docker-compose, we can set the DOCKER_HOST env var:

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$ export DOCKER_HOST=172.17.0.1 && docker-compose

In MacOS and Windows, we don’t need to set this variable, and can just do:

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$ docker-compose

Other: check docker network interface

  • List all network interface: docker network ls
  • Inspect a network interface: e.g. docker network inspect bridge, docker network inspect host

Reference