Automatic setup with cloud-init

Authored by Carlos Nihelton (carlos.santanadeoliveira@canonical.com)

Cloud-init is an industry-standard multi-distribution method for cross-platform cloud instance initialisation. Ubuntu WSL users can now leverage it to perform an automatic setup to get a working instance with minimal touch.

The latest release of Ubuntu (Noble Numbat 24.04 LTS) comes with cloud-init already preinstalled, so you’ll need that specific application to follow this tutorial. Ubuntu 24.04 LTS can be installed from this link to the Microsoft Store. A previous version of this tutorial used Ubuntu (Preview), because that comes with the latest in-development features. You can still use it to follow the instructions below, if you prefer. This feature is now available in the default Ubuntu application as well as Ubuntu 22.04 LTS.

What you will learn

  • How to write cloud-config user data to a specific WSL instance.

  • How to automatically set up a WSL instance with cloud-init.

  • How to verify that cloud-init succeeded with the configuration supplied.

What you will need

  • Windows 11 with WSL 2 already enabled

  • The latest Ubuntu 24.04 LTS application from the Microsoft Store

Write the cloud-config file

Locate your Windows user home directory. It typically is C:\Users\<YOUR_USER_NAME>.

You can be sure about that path by running echo $env:USERPROFILE in PowerShell.

Inside your Windows user home directory, create a new folder named .cloud-init (notice the . à la Linux configuration directories), and inside the new directory, create an empty file named Ubuntu-24.04.user-data. That file name must match the name of the distro instance that will be created in the next step.

Open that file with your text editor of choice (notepad.exe is just fine) and paste in the following contents:

#cloud-config
locale: pt_BR
users:
- name: jdoe
  gecos: John Doe
  groups: [adm,dialout,cdrom,floppy,sudo,audio,dip,video,plugdev,netdev]
  sudo: ALL=(ALL) NOPASSWD:ALL
  shell: /bin/bash

write_files:
- path: /etc/wsl.conf
  append: true
  content: |
    [user]
    default=jdoe

packages: [ginac-tools, octave]

runcmd:
   - sudo git clone https://github.com/Microsoft/vcpkg.git /opt/vcpkg
   - sudo apt-get install zip curl -y
   - /opt/vcpkg/bootstrap-vcpkg.sh

Save it and close it.

That example will create a user named jdoe and set it as default via /etc/wsl.conf, install the packages ginac-tools and octave and install vcpkg from the git repository, since there is no deb or snap of that application (hence the reason for being included in this tutorial - it requires an unusual setup).

Register a new Ubuntu-24.04 instance

In PowerShell, run:

> ubuntu2404.exe

This command will register a new Ubuntu-24.04 instance that will be configured automatically by cloud-init. The process can take several minutes, depending on your computer and network speeds.

If you want to be sure that there is now an Ubuntu-24.04 instance, run wsl -l -v. Notice that the application is named Ubuntu24.04LTS but the WSL instance created is named Ubuntu-24.04. See more about that naming convention in our reference documentation.

Verify automatic configuration by cloud-init

When the setup is complete, the WSL instance’s shell will be logged in as the user jdoe. You should see the standard welcome text:

Installing, this may take a few minutes...
Installation successful!
To run a command as administrator (user "root"), use "sudo <command>".
See "man sudo_root" for details.

Welcome to Ubuntu 24.04.1 LTS (GNU/Linux 6.6.36.3-microsoft-standard-WSL2 x86_64)

 * Documentation:  https://help.ubuntu.com
 * Management:     https://landscape.canonical.com
 * Support:        https://ubuntu.com/pro

 System information as of ter 01 out 2024 14:32:47 -03

  System load:  1.64                Processes:             63
  Usage of /:   0.2% of 1006.85GB   Users logged in:       0
  Memory usage: 4%                  IPv4 address for eth0: 172.22.8.90
  Swap usage:   0%


This message is shown once a day. To disable it please create the
/home/jdoe/.hushlogin file.
jdoe@mib01:~$

Once logged into the new distro instance’s shell, verify that:

  1. The default user matches what was configured in the user data file (in our case jdoe).

jdoe@mib:~$ whoami

This should be verified with the output message:

jdoe

  1. The supplied cloud-config user data was approved by cloud-init validation.

jdoe@mib:~$ sudo cloud-init schema --system

Verified with the output:

Valid schema user-data

  1. The locale is set

jdoe@mib:~$ locale

Verified with:

LANG=pt_BR
LANGUAGE=
LC_CTYPE="pt_BR"
LC_NUMERIC="pt_BR"
LC_TIME="pt_BR"
LC_COLLATE="pt_BR"
LC_MONETARY="pt_BR"
LC_MESSAGES="pt_BR"
LC_PAPER="pt_BR"
LC_NAME="pt_BR"
LC_ADDRESS="pt_BR"
LC_TELEPHONE="pt_BR"
LC_MEASUREMENT="pt_BR"
LC_IDENTIFICATION="pt_BR"
LC_ALL=

  1. The packages were installed and the commands they provide are available.

jdoe@mib:~$ apt list --installed | egrep 'ginac|octave'

Verified:

WARNING: apt does not have a stable CLI interface. Use with caution in scripts.

ginac-tools/noble,now 1.8.7-1 amd64 [installed]
libginac11/noble,now 1.8.7-1 amd64 [installed,automatic]
octave-common/noble,now 8.4.0-1 all [installed,automatic]
octave-doc/noble,now 8.4.0-1 all [installed,automatic]
octave/noble,now 8.4.0-1 amd64 [installed]

  1. Lastly, verify that the commands requested were also run. In this case we set up vcpkg from git, as recommended by its documentation (there is no deb or snap available for that program).

jdoe@mib:~$ /opt/vcpkg/vcpkg version

This should also be verified with:

vcpkg package management program version 2024-01-11-710a3116bbd615864eef5f9010af178034cb9b44

See LICENSE.txt for license information.

Enjoy!

That’s all folks! In this tutorial, we’ve shown you how to use cloud-init to automatically set up Ubuntu on WSL 2 with minimal touch.

This workflow will guarantee a solid foundation for your next Ubuntu WSL project.

We hope you enjoy using Ubuntu inside WSL!