Adding a new user in Ubuntu using cloud init fails

Question

I'm trying to set up some defaults for several of my Ubuntu machines running the Ubuntu 22.04 server. Here is my config:

#cloud-config
ssh_pwauth: false

groups:
  - mygrp

users:
  - name: myuser
    gecos: myuser
    sudo: ALL=(ALL) NOPASSWD:ALL
    groups: [mygrp, sudo]
    ssh_import_id: None
    lock_passwd: true
    shell: /bin/bash
    # Replace the <ssh-pub-key> with the actual SSH public key
    ssh_authorized_keys:
      - <ssh-pub-key>
    
preserve_hostname: false
hostname: open-electrons-m1
manage_etc_hosts: true

# If this is set, 'root' will not be able to ssh in and they
# will get a message to login instead as the default $user
disable_root: true

What is wrong with this script that I have? I do not see any issues in the cloud-init.log. No error messages. After running:

cloud-init init

Running this command:

cat /etc/hostname

is not printing my-host-name

The user is also not created. What is happening with this script? I'm breaking my head around this!

Answer 1

After running cloud-init init

This is not how cloud-init works. Cloud-init runs multiple times on boot as part of many different systemd services. Additionally, most modules that run during first boot are set to not run again, even if cloud-init runs again. You wouldn't want cloud-init attempting to recreate a new user every single boot, so cloud-init won't attempt to create users again unless it is specifically requested to. See the boot stage docs for more info on the cloud-init boot stages.

If you're trying to emulate cloud-init's first-boot behavior, you have a couple of different options. The safest way is to install LXD and launch a new container from there. If your cloud-config has already been supplied to the instance, you can run the cloud-init commands manually. I would only run this in a container/VM as it could make destructive changes to your system:

cloud-init clean --logs
cloud-init init --local
cloud-init init
cloud-init modules --mode=config
cloud-init modules --mode=final
cloud-init status --wait --long

Using LXD, I ran your config and it seems to work mostly as expected:

root@me:~# cat /etc/hostname
open-electrons-m1
root@me:~# grep "myuser" /etc/passwd
myuser:x:1000:1001:myuser:/home/myuser:/bin/bash

There's still some problems with the cloud-config though. According the users and groups module

Groups are added before users, so any users in a group list must already exist on the system.

So your user cannot be added to the mygrp group. Also None isn't a valid value for ssh_import_id. You can remove that line entirely.