Docker throws weight behind Windows Subsystem for Linux, chucks Hyper-V option overboard

Docker has thrown its support behind Microsoft’s latest rev of the Windows Subsystem for Linux, promising a technical review of Docker Desktop for WSL-2 next month.

In a blog post yesterday, Docker’s Simon Ferquel, wrote that while the original WSL was “an impressive effort to emulate a Linux Kernel on top of Windows”, the fundamental differences were such that “it was impossible to run the Docker Engine and Kubernetes directly inside WSL.”

Docker had, consequently, developed “an alternative solution” using Hyper-V and LinuxKit.

However, the container innovator said that the new version, unveiled last month, delivered “a real Linux Kernel running inside a lightweight VM. This approach is architecturally very close to what we do with LinuxKit and Hyper-V today, with the additional benefit that it is more lightweight and more tightly integrated with Windows than Docker can provide alone.”

Consequently, wrote Ferquel, “We will replace the Hyper-V VM we currently use by a WSL 2 integration package.” He said this approach would provide the same features as the current approach: “Kubernetes 1-click setup, automatic updates, transparent HTTP proxy configuration, access to the daemon from Windows, transparent bind mounts of Windows files, and more.”

When it came to running Linux, he continued, “With WSL 2 integration, you will still experience the same seamless integration with Windows, but Linux programs running inside WSL will also be able to do the same.”

This would remove the need for running separate Linux and Windows build scripts, he continued, and “a developer at Docker can now work on the Linux Docker daemon on Windows, using the same set of tools and scripts as a developer on a Linux machine.”

The technical preview, “will run side by side with the current version of Docker Desktop, so you can continue to work safely on your existing projects. If you are running the latest Windows Insider build, you will be able to experience this first hand.”

Further features will be added over the coming months, “until the WSL 2 architecture is used in Docker Desktop for everyone running a compatible version of Windows.”

Microsoft and Docker have gotten steadily closer over the last year. The container outfit’s Docker Enterprise product has been tweaked to support ageing Windows architectures, giving Redmond’s customers a reason NOT to consider alternative platforms. At the same time, they have collaborated on specifications for running distributed applications.