Microsoft adds a Linux kernel to Windows with WSL 2, Canonical announces support

Will support FUSE and Docker

Microsoft has announced a new version of its Windows Subsystem for Linux compatibility layer which allows users to run Linux programs natively on Windows 10 and Windows Server 2019.

WSL 2, which will be available in June with source code published on Github, features a VM-based architecture and a Linux kernel, along with integrated Windows file sharing capabilities and enterprise support.

The original WSL, released two years ago for Windows 10 and Windows Server, contained no Linux code, Instead it plugged into the NT kernel. WSL 1 allowed users to run Linux programs more quickly than was possible in VMs or on previous compatibility efforts such as Lin4Win, but it was limited to specific applications (Docker did not run properly, for example) and fine-tuning performance proved to be a challenge. WSL 2 addresses the Linux-NT compatibility issues by including a performance-optimised version of the Linux kernel that supports many more applications, including Docker and FUSE.

"WSL 2 uses an entirely new architecture that uses a real Linux kernel," says Microsoft developer Craig in a blog post. "Yes, you did just read that heading correctly! We will be shipping a real Linux kernel with Windows that will make full system call compatibility possible."

Craig continued. "It will still give the remarkable benefits of WSL 1: High levels of integration between Windows and Linux, extremely fast boot times, small resource footprint, and best of all will require no VM configuration or management."

A demo on the blog post shows a working bash shell starting in less than 2 seconds. File-intensive operations such as git clone, npm install, apt update, apt upgrade will all be noticeably faster than with the previous WSL, it claims.

In a press release, Stephan Fabel, director of product at Linux vendor Canonical, welcomed the announcement.

"Extending enterprise support for Ubuntu from Azure to Windows workstations and servers creates a seamless operating environment for Ubuntu in the Microsoft environment," he said. "Collaboration with Microsoft enables us to certify Ubuntu on WSL, including Docker containers, Kubernetes and snaps".

The virtualisation and Linux kernel will align Ubuntu on Azure with Ubuntu on workstations and servers, allowing Canonical to provide enterprise certification and support, the company said.

WSL 2 will also support other Linux distributions, including Suse, Debian, and more.