Automating First Boot with Cloud-init & User Data

Cloud-init is the industry standard for customizing cloud instances during their very first boot. It allows you to configure users, install software, and run scripts automatically without ever logging in manually.

At Tilaa, all our Linux images come with Cloud-init pre-installed. You can supply your configuration via the "User Data" field during deployment (via the Dashboard or API).

Supported Operating Systems

Cloud-init is available on all our standard Linux distributions:

• Ubuntu / Debian
• AlmaLinux / Rocky Linux / CentOS
• Arch Linux

Writing a Cloud-Config Script

The most common format for User Data is YAML. It must always start with the line #cloud-config.

Example 1: Basic User Setup

This script creates a new user, gives them sudo rights, and adds an SSH key.

#cloud-config
users:
  - name: deployuser
    groups: sudo, wheel
    shell: /bin/bash
    sudo: ['ALL=(ALL) NOPASSWD:ALL']
    ssh_authorized_keys:
      - ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQC... (your key here)
    lock_passwd: true

Example 2: Install Software (Web Server)

This script updates the system, installs Apache, and creates a default index page.

#cloud-config
package_update: true
package_upgrade: true

packages:
  - httpd
  - php

runcmd:
  - systemctl enable httpd
  - systemctl start httpd
  - echo "Hello World from Cloud-init" > /var/www/html/index.html

How to Apply User Data

• Dashboard: In the VPS Configurator, look for the "User Data" or "Cloud-init" text area during the checkout process. Paste your script there.
• API: When creating an instance via the API, pass your script (Base64 encoded) in the user_data field.

Troubleshooting

If your script didn't do what you expected, you can check the logs inside the server to see what went wrong.

1. Check the output log:
This shows the console output of your commands.

cat /var/log/cloud-init-output.log

2. Check the processing log:
This shows parsing errors (e.g., invalid YAML).

cat /var/log/cloud-init.log