Create Finalization Templates

In PaletteAI VM Launchpad, finalization templates define seal and generalize scripts for golden image finalization. They prepare the OS for cloning by removing machine-specific data and assigning a unique identity to each clone. Create custom finalization templates for other Linux distributions, such as Alpine, Arch, and SUSE. You can also create custom templates when you need to modify seal logic, include cleanup scripts, include custom scripts, or complete security hardening and compliance checks.

Finalization Templates

A finalization template is a reusable script (or script reference) that runs inside the builder VM during the Finalize step. The script:

• Cleans cloud-init state, SSH host keys, machine-id, logs, and caches.
• Removes network persistence, such as udev rules and DHCP leases.
• Runs sysprep with generalize and shutdown for Windows.
• Prepares the image for cloning without identity conflicts.

VM Launchpad stores finalization templates as CRDs and manages them under Image Catalog > Finalize Templates.

Built-in Finalize Templates

VM Launchpad includes built-in finalization templates.

Template	OS Type	Description
RHEL / CentOS / Fedora	rhel/centos	Generalize the RHEL family: cloud-init cleanup, unregister subscription-manager, remove SSH host keys, truncate machine-id.
Ubuntu / Debian	ubuntu/debian	Generalize Ubuntu or Debian: cloud-init cleanup, remove SSH host keys, truncate machine-id, clear logs and history.
Windows	windows	Generalize Windows: run sysprep with /generalize /oobe /shutdown. Also installs QEMU guest agent from the VM Launchpad package server before sysprep.

You can reference built-in templates when you create custom templates. VM Launchpad prevents deletion of built-in templates.

Create a Custom Template

1. Navigate to Image Catalog > Finalize Templates.

2. Select Create Template.

3. Complete the following fields on the Create Finalize Template page and select Create.

   Parameter	Description
   Name	Enter a unique name for the template.
   Description	Enter a description for the template.
   OS Type	linux, windows, ubuntu, rhel, or another supported value. VM Launchpad uses this value to filter templates during finalization.
   Script	Select the option on how to add the script: Editor, Template, Upload, or URL.

The finalization template is available on the Finalize Template page.

Script Behavior by OS

OS	Script Type	Requirements
Linux	Bash	Must complete successfully. Avoid shell options that stop the script after the first error if you need partial cleanup to succeed. The script runs as root. End with sync and a clear completion message.
Windows	Batch or PowerShell	Must run sysprep or another generalization tool. The built-in Windows template uses sysprep with /generalize /oobe /shutdown.

Apply Templates during Finalization

When you select Finalize on a builder VM, VM Launchpad applies the template in the following order.

1. The finalization page loads available finalization templates.
2. VM Launchpad filters templates by OS Type. It infers the guest OS from the builder VM or uses the value you select.
   • ubuntu/debian builders display Ubuntu/Debian and generic Linux templates.
   • rhel/centos/fedora builders display RHEL-family templates.
   • windows builders display Windows templates.
   • other builders display any templates for a guest OS not supported by the other templates.
3. You select a finalization template (or "None" for basic finalization).
4. The system stops the VM, ejects media, starts the VM, waits for the guest agent, and then runs the selected template's script through cloud-init or a similar mechanism.
5. When the script completes, the system stops the VM and cleans up the builder. The DataVolume is the sealed golden image.

Template Selection Priority

When you open the finalization page, the system picks a default template in this order.

1. Pre-selected from builder: If the builder VM has an annotation with a template ID, the system selects that template.
2. Match by guest OS: The first template whose osType matches the guest OS. For example, ubuntu matches Ubuntu and windows matches Windows.
3. First built-in: The first built-in template.
4. First available: The first template in the list.

You can override the selection before starting finalization.

Auto-Install Scripts

Auto-install scripts differ from finalization templates. They run during OS installation (first boot of the builder VM), not during finalization.

OS	Format	Purpose
Linux	Cloud-init YAML	preseed, kickstart, or cloud-init autoinstall to automate OS installation.
Windows	Autounattend.xml	Unattended installation answers (product key, disk partitioning, user creation).

VM Launchpad manages auto-install scripts under Image Catalog > Auto Install Scripts. The page lists each script with its name, OS type, and description. When building a golden image, you select an auto-install script to inject into the builder VM's cloud-init or to attach as Autounattend.xml. Set a script as the OS default to auto-populate the builder for that OS.

Built-in Auto Install Scripts

VM Launchpad includes built-in auto-install scripts.

Script	OS Type	Description
RHEL / CentOS Kickstart	RHEL / CentOS	Minimal Kickstart configuration for unattended RHEL or CentOS installation.
Ubuntu Autoinstall (Jammy-only)	Ubuntu / Debian	Cloud-init autoinstall configuration for unattended Ubuntu Server installation. The airgap variant targets Ubuntu 22.04 (Jammy) only, while the connected variant works across Ubuntu releases.
Windows Unattend (legacy)	Windows	Basic Autounattend.xml for unattended Windows installation with OOBE bypass.
Windows 11 / Server 2022+ Autounattend	Windows	Autounattend.xml for unattended Windows 11 and Windows Server 2022 or newer installation, with EFI partitioning and OOBE bypass.

You can reference or copy a built-in script when you create your own.

Create an Auto Install Script

1. Navigate to Image Catalog > Auto Install Scripts.

2. Select Create Script.

3. Complete the following fields in the Create Auto Install Script dialog and select Create.

   Parameter	Description
   Name	Enter a unique name for the script.
   Description	Enter an optional description for the script.
   OS Type	Select the target OS, such as RHEL / CentOS, Ubuntu / Debian, or Windows. Select Custom for another OS.
   OS Default	Select this option to set the script as the default for its OS type. VM Launchpad auto-populates the script in the builder when you build a golden image for that OS.
   Script	Select how to add the script: Editor, Template, Upload, or URL. Linux scripts use cloud-init YAML, and Windows scripts use Autounattend.xml.
   Network Data	Optionally provide Netplan network configuration to apply during installation.

How Templates and Auto-Install Work Together

1. Build: The golden image builder VM boots with an ISO and auto-install script. The OS installs unattended.
2. Finalize: After the OS is installed, you apply a finalization template. The seal script generalizes the image.

Use auto-install scripts to install the OS. Use finalization templates to prepare the image for cloning.