Privileged configurations are applied during the installation with the `--user` flag on the [install command](/manuals/desktop/setup/install/mac-install.md#install-from-the-command-line). In this case, you are not prompted to grant root privileges on the first run of Docker Desktop. Specifically, the `--user` flag:
- Uninstalls the previous `com.docker.vmnetd` if present
- Sets up symlinks
- Ensures that `localhost` is resolved to `127.0.0.1`

The limitation of this approach is that Docker Desktop can only be run by one user-account per machine, namely the one specified in the `-–user` flag.

## Privileged helper

In the limited situations when the privileged helper is needed, for example binding privileged ports or caching the Registry Access Management policy, the privileged helper is started by `launchd` and runs in the background unless it is disabled at runtime as previously described. The Docker Desktop backend communicates with the privileged helper over the UNIX domain socket `/var/run/com.docker.vmnetd.sock`. The functionalities it performs are:
- Binding privileged ports that are less than 1024.
- Securely caching the Registry Access Management policy which is read-only for the developer.
- Uninstalling the privileged helper.

The removal of the privileged helper process is done in the same way as removing `launchd` processes.

```console
$ ps aux | grep vmnetd
root             28739   0.0  0.0 34859128    228   ??  Ss    6:03PM   0:00.06 /Library/PrivilegedHelperTools/com.docker.vmnetd
user             32222   0.0  0.0 34122828    808 s000  R+   12:55PM   0:00.00 grep vmnetd

$ sudo launchctl unload -w /Library/LaunchDaemons/com.docker.vmnetd.plist
Password:

$ ps aux | grep vmnetd
user             32242   0.0  0.0 34122828    716 s000  R+   12:55PM   0:00.00 grep vmnetd

$ rm /Library/LaunchDaemons/com.docker.vmnetd.plist

$ rm /Library/PrivilegedHelperTools/com.docker.vmnetd
```

## Containers running as root within the Linux VM

With Docker Desktop, the Docker daemon and containers run in a lightweight Linux
VM managed by Docker. This means that although containers run by default as
`root`, this doesn't grant `root` access to the Mac host machine. The Linux VM
serves as a security boundary and limits what resources can be accessed from the
host. Any directories from the host bind mounted into Docker containers still
retain their original permissions.

## Enhanced Container Isolation

In addition, Docker Desktop supports [Enhanced Container Isolation
mode](/manuals/security/for-admins/hardened-desktop/enhanced-container-isolation/_index.md) (ECI),
available to Business customers only, which further secures containers without
impacting developer workflows.

ECI automatically runs all containers within a Linux user-namespace, such that
root in the container is mapped to an unprivileged user inside the Docker
Desktop VM. ECI uses this and other advanced techniques to further secure
containers within the Docker Desktop Linux VM, such that they are further
isolated from the Docker daemon and other services running inside the VM.