PowerShell script that creates a Ubuntu VM template.

install-pwsh.sh

#!/bin/bash
wget https://packages.microsoft.com/config/debian/11/packages-microsoft-prod.deb
dpkg -i packages-microsoft-prod.deb
apt-get update -y
apt-get install -y powershell
# pwsh -c ". ./New-QemuTemplate.ps1"

New-QemuTemplate.ps1

#!/usr/bin/pwsh
[CmdletBinding()]
param (
    [Parameter()]
    [string]
    $ReleaseName = "focal",
    [Parameter()]
    [string]
    $Architecture = "amd64",
    [Parameter()]
    [string]
    $IsoFolder = "/var/lib/vz/template/iso",
    [Parameter()]
    [string]
    $TemplateName = "ubuntu-2004-cloudinit-template",
    [Parameter()]
    [int]
    $Memory = 4096,
    [Parameter()]
    [int]
    $Cores = 2,
    [Parameter()]
    [string]
    $NetworkDriver = "virtio",
    [Parameter()]
    [string]
    $NetworkBridge = "vmbr1",
    [Parameter()]
    [string]
    $StorageName = "local-zfs",
    [Parameter()]
    [string[]]
    $Packages = "qemu-guest-agent"
)

$Arch = $Architecture

$ImageFileName = "$ReleaseName-server-cloudimg-$Arch.img"
$Template = [PSCustomObject]@{
    Name   = $TemplateName
    Memory = $Memory
    Cores  = $Cores
    Net    = [PSCustomObject]@{
        Driver = $NetworkDriver
        Bridge = $NetworkBridge
    }
}
$Packages = $Packages -join ','

$LastVMId = Get-ChildItem -Path "/etc/pve/nodes/pve/qemu-server/" |
Select-Object -Property Name |
ForEach-Object { $_.Name -replace '.conf' } |
Select-Object -Last 1

$VmId = ($LastVMId -as [int]) + 1
$QmPath = (Get-Command -Name "qm").Source
$VirtCustomizePath = (Get-Command -Name "virt-customize").Source
$AptGet = (Get-Command -Name "apt-get").Source
# download the cloud image 
$Splat = @{
    Uri     = "https://cloud-images.ubuntu.com/$ReleaseName/current/$ImageFileName"
    OutFile = "$IsoFolder/$ImageFileName"
}
Invoke-WebRequest @Splat
. $AptGet -y install libguestfs-tools
. $VirtCustomizePath -a $ImageFileName --install $Packages
. $QmPath create $VmId --name $Template.Name --memory $Template.Memory --cores $Template.Cores --net0 $Template.Net.Driver, bridge=$Template.Net.Bridge
. $QmPath importdisk $VmId $ImageFileName $StorageName
. $QmPath set $VmId --scsihw virtio-scsi-pci --scsi0 $($StorageName):vm-$VmId-disk-0
. $QmPath set $VmId --ide2 $($StorageName):cloudinit
. $QmPath set $VmId --boot c --bootdisk scsi0
. $QmPath set $VmId --serial0 socket --vga serial0
# Setting agent to 1 might error out
. $QmPath set $VmId --agent enabled=1, type=virtio

"If no errors, run the following to convert the VM to a template:"
"qm template $VmId"