Creating Additional WSL2 Instances

Get a rootfs. e.g. Ubuntu rootfs: https://wiki.ubuntu.com/WSL#Installing_Ubuntu_on_WSL_via_rootfs

wsl.conf settings - https://docs.microsoft.com/en-us/windows/wsl/wsl-config#configure-per-distro-launch-settings-with-wslconf

Configure global options with .wslconfig - https://docs.microsoft.com/en-us/windows/wsl/wsl-config#configure-global-options-with-wslconfig

Creating a Custom Distribution

The first thing we’ll need is a root filesystem. Luckily Ubuntu make their WSL root filesystem available for download, which is available here. For this walk-through I’ve created a directory on my Windows C: drive called “wsl”, we’ll place the rootfs files in c:\wsl\wslrootfs and the distros in c:\wsl\wsldistros\

• Download the file above to the wslrootfs directory.

• Run wsl.exe --import base-ubuntu C:\wsl\wsldistros\base-ubuntu\ C:\wsl\wslrootfs\ubuntu-20.04-server-cloudimg-amd64-wsl.rootfs.tar.gz

In this command base-ubuntu Is just a name you want to assign so for example a specific project. c:\wsl\wsldistros\base-ubuntu\ is the directory on your machine you want to place the virtual disk file for the distribution and then we have the distro file we downloaded

At this point you have a clean install of ubuntu 20.04 to use. You can then easily access each distribution you have available with Windows Terminal which places them all on a tab drop-down for easy access.

Configure the base

Configure it however you please. Consider using something like Ansible if this is going to be a fairly common process for you.

At this point, I'm specifying my naming convention moving forward. <date-modified>-<type>-<distro>

• 20200714-base-ubuntu

Using our WSL distro as a template

Once we’ve got the tooling we want installed, we can export the rootfs for later use.

wsl --export baseubu c:\wsl\wslrootfs\20200714-base-ubuntu

Then we can create new instances based off this by importing the 20200714-base-ubuntu file we just created

wsl --import ViciousUnicorn c:\wsl\wsldistros\ViciousUnicorn\ c:\wsl\wslrootfs\20200714-base-ubuntu

and when we start it up, all our tools are in place :)

Cleaning up

Once you’re finished with it, it can just be removed with wsl.exe --unregister <Name>. This will delete the virtual disk file, however, as of writing the created folder is left behind.

Acknowledgement

Credit to Rory: https://raesene.github.io/blog/2020/05/31/Custom_Pentest_Distributions_With_WSL2/