source: /run/host-services/ssh-auth.sock
        target: /run/host-services/ssh-auth.sock
    environment:
      - SSH_AUTH_SOCK=/run/host-services/ssh-auth.sock
 ```

## Known limitations

### Changing internal IP addresses

The internal IP addresses used by Docker can be changed from **Settings**. After changing IPs, you need to reset the Kubernetes cluster and to leave any active Swarm.

### There is no `docker0` bridge on the host

Because of the way networking is implemented in Docker Desktop, you cannot
see a `docker0` interface on the host. This interface is actually within the
virtual machine.

### I cannot ping my containers

Docker Desktop can't route traffic to Linux containers. However if you're a Windows user, you can
ping the Windows containers.

### Per-container IP addressing is not possible

This is because the Docker `bridge` network is not reachable from the host.
However if you are a Windows user, per-container IP addressing is possible with Windows containers.

## Use cases and workarounds 

### I want to connect from a container to a service on the host

The host has a changing IP address, or none if you have no network access.
Docker recommends you connect to the special DNS name `host.docker.internal`,
which resolves to the internal IP address used by the host.

You can also reach the gateway using `gateway.docker.internal`.

If you have installed Python on your machine, use the following instructions as an example to connect from a container to a service on the host:

1. Run the following command to start a simple HTTP server on port 8000.

    `python -m http.server 8000`

    If you have installed Python 2.x, run `python -m SimpleHTTPServer 8000`.

2. Now, run a container, install `curl`, and try to connect to the host using the following commands:

    ```console
    $ docker run --rm -it alpine sh
    # apk add curl
    # curl http://host.docker.internal:8000
    # exit
    ```

### I want to connect to a container from the host

Port forwarding works for `localhost`. `--publish`, `-p`, or `-P` all work.
Ports exposed from Linux are forwarded to the host.

Docker recommends you publish a port, or to connect from another
container. This is what you need to do even on Linux if the container is on an
overlay network, not a bridge network, as these are not routed.

For example, to run an `nginx` webserver:

```console
$ docker run -d -p 80:80 --name webserver nginx
```

To clarify the syntax, the following two commands both publish container's port `80` to host's port `8000`:

```console
$ docker run --publish 8000:80 --name webserver nginx

$ docker run -p 8000:80 --name webserver nginx
```

To publish all ports, use the `-P` flag. For example, the following command
starts a container (in detached mode) and the `-P` flag publishes all exposed ports of the
container to random ports on the host.

```console
$ docker run -d -P --name webserver nginx
```

Alternatively, you can also use [host networking](/manuals/engine/network/drivers/host.md#docker-desktop)
to give the container direct access to the network stack of the host.

See the [run command](/reference/cli/docker/container/run.md) for more details on
publish options used with `docker run`.