---
title: Limitations
description: Limitations of Enhanced Container Isolation
keywords: enhanced container isolation, security, sysbox, known issues, Docker Desktop
toc_max: 2
---

### ECI support for WSL

Prior to Docker Desktop 4.20, Enhanced Container Isolation (ECI) on
Windows hosts was only supported when Docker Desktop was configured to use
Hyper-V to create the Docker Desktop Linux VM. ECI was not supported when Docker
Desktop was configured to use Windows Subsystem for Linux (aka WSL).

Starting with Docker Desktop 4.20, ECI is supported when Docker Desktop is
configured to use either Hyper-V or WSL version 2.

>**Note**
>
> Docker Desktop requires WSL 2 version 1.1.3.0 or later. To get the current
> version of WSL on your host, type `wsl --version`. If the command fails or if
> it returns a version number prior to 1.1.3.0, update WSL to the latest version
> by typing `wsl --update` in a Windows command or PowerShell terminal.

Note however that ECI on WSL is not as secure as on Hyper-V because:

* While ECI on WSL still hardens containers so that malicious workloads can't
  easily breach Docker Desktop's Linux VM, ECI on WSL can't prevent Docker
  Desktop users from breaching the Docker Desktop Linux VM. Such users can
  trivially access that VM (as root) with the `wsl -d docker-desktop` command,
  and use that access to modify Docker Engine settings inside the VM. This gives
  Docker Desktop users control of the Docker Desktop VM and allows them to
  bypass Docker Desktop configs set by admins via the
  [settings-management](../settings-management/index.md) feature. In contrast,
  ECI on Hyper-V does not allow Docker Desktop users to breach the Docker
  Desktop Linux VM.

* With WSL 2, all WSL 2 distros on the same Windows host share the same instance
  of the Linux kernel. As a result, Docker Desktop can't ensure the integrity of
  the kernel in the Docker Desktop Linux VM since another WSL 2 distro could
  modify shared kernel settings. In contrast, when using Hyper-V, the Docker
  Desktop Linux VM has a dedicated kernel that is solely under the control of
  Docker Desktop.

The table below summarizes this.

| Security Feature                                   | ECI on WSL   | ECI on Hyper-V   | Comment               |
| -------------------------------------------------- | ------------ | ---------------- | --------------------- |
| Strongly secure containers                         | Yes          | Yes              | Makes it harder for malicious container workloads to breach the Docker Desktop Linux VM and host. |
| Docker Desktop Linux VM protected from user access | No           | Yes              | On WSL, users can access Docker Engine directly or bypass Docker Desktop security settings. |
| Docker Desktop Linux VM has a dedicated kernel     | No           | Yes              | On WSL, Docker Desktop can't guarantee the integrity of kernel level configs. |

In general, using ECI with Hyper-V is more secure than with WSL 2. But WSL 2
offers advantages for performance and resource utilization on the host machine,
and it's an excellent way for users to run their favorite Linux distro on
Windows hosts and access Docker from within (see Docker Desktop's WSL distro
integration feature, enabled via the Dashboard's **Settings** > **Resources** > **WSL Integration**).

### Docker Build and Buildx have some restrictions
With ECI enabled, Docker build `--network=host` and Docker Buildx entitlements
(`network.host`, `security.insecure`) are not allowed. Builds that require
these won't work properly.

### Kubernetes pods are not yet protected
Kubernetes pods are not yet protected by ECI. A malicious or privileged pod can
compromise the Docker Desktop Linux VM and bypass security controls.

### Extension containers are not yet protected
Extension containers are also not yet protected by ECI. Ensure you extension
containers come from trusted entities to avoid issues.

### Docker Desktop dev environments are not yet protected
Containers launched by the Docker Desktop Dev Environments feature are not yet
protected either. We expect to improve on this in future versions of Docker
Desktop.

### Use in production
In general users should not experience differences between running a container
in Docker Desktop with ECI enabled, which uses the Sysbox runtime, and running
that same container in production, through the standard OCI `runc` runtime.

However in some cases, typically when running advanced or privileged workloads in
containers, users may experience some differences. In particular, the container
may run with ECI but not with `runc`, or vice-versa.
