Install on WSL

Windows 10 has a subsystem that emulates the Linux kernel interface to allow ordinary Linux applications to run. It is somewhat like the opposite of Wine, but at a lower level. By default it comes with Ubuntu user space, but that can be replaced with Arch. To get it working properly you will require access to an existing Arch installation to build some packages. These instructions are based on this guide.

Warning: A WSL install is NOT an Arch Linux installation, so is not supported in the Arch Community support channels.

Preparation

Note: If you have used WSL prior to the Fall Creators Update, uninstall it first from the command prompt (you might want to save some data first):

> lxrun /uninstall /full /y

If you are running the Windows 10 Fall Creators Update or later, enable "Windows Subsystem for Linux" in Turn Windows features on or off.

If you are on the Anniversary Update or Creators Update, follow the instructions here to enable it.

Installation

Note: If you're using a Windows version older than the Fall Creators Update, use %localappdata%\lxss\rootfs instead of %localappdata%\Packages\CanonicalGroupLimited.UbuntuonWindows_*\LocalState\rootfs.

Install Ubuntu from the Windows Store.

Start Ubuntu from the Start Menu.

Make sure the Default user is root:

$ ubuntu config --default-user root

Download an Arch bootstrap .tar.gz from Arch Linux Downloads, and extract it:

$ tar -zxvf /mnt/c/Users/username/Downloads/archlinux-bootstrap-version.tar.gz

Uncomment a server in ~/root.x86_64/etc/pacman.d/mirrorlist.

Make WSL autogenerate /etc/resolv.conf:

$ echo "# This file was automatically generated by WSL. To stop automatic generation of this file, remove this line." > ~/root.x86_64/etc/resolv.conf

Exit all bash prompts you have open.

In the Windows explorer, navigate to %localappdata%\Packages and look for a folder called CanonicalGroupLimited.UbuntuonWindows_* where the asterisk is a random string.

From %localappdata%\Packages\CanonicalGroupLimited.UbuntuonWindows_*\LocalState\rootfs, delete bin, etc, lib, lib64, sbin, usr and var.

Now move (do not copy) the same folders from rootfs\root\root.x86_64 to rootfs

Using a Linux computer build fakeroot-tcp^AUR and glibc-wsl^AUR. Note that --nocheck can be used with makepkg to skip a very time-consuming test suite when building glibc-wsl^AUR.

Then copy the packages to your Windows PC. glibc-wsl has a workaround for this bug, and fakeroot-tcp is necessary until System V IPC is fully implemented (see here). This step will be unnecessary when those bugs are fixed.

Open bash again, and setup Arch:

# pacman-key --init
# pacman-key --populate archlinux
# pacman -U /mnt/c/Users/username/Downloads/glibc-wsl-2.25-2-x86_64.pkg.tar.xz
# pacman -U /mnt/c/Users/username/Downloads/fakeroot-tcp-1.21-2-x86_64.pkg.tar.xz
# pacman -Syyu base base-devel

Set up a user (does not have to be the same as your Windows username):

# useradd -m -G wheel -s /bin/bash username
# passwd root
# passwd username

Set the user as the default by running the following in a Windows command prompt:

Note: If you are running the Windows 10 Fall Creators Update or later, use this command: ubuntu config --default-user username

> lxrun /setdefaultuser username