Create a LiveOS ISO and run it in a VM

This guide demonstrates how to use Image Customizer to build an Azure Linux LiveOS ISO and then run it in a local VM.

A LiveOS image is an OS image that can be booted from media (e.g. CDROM, USB) without needing to install the OS.

Build LiveOS ISO

  1. Create image config file.

    The following config file creates a service that runs after boot and prints a message to the system console:

    # config.yaml
os:
  # Install ISO required packages
  packages:
    install:
    - squashfs-tools
    - tar
    - device-mapper
    - curl

  additionalFiles:
  - destination: /usr/local/lib/systemd/system/myservice.service
    content: |
      [Unit]
      Description=My Service

      [Service]
      Type=exec
      ExecStart=/usr/local/bin/myservice.sh
      # Print to the system console.
      StandardOutput=journal+console

      [Install]
      WantedBy=multi-user.target

  - destination: /usr/local/bin/myservice.sh
    permissions: 755
    content: |
      #!/usr/bin/env bash
      set -eu

      # Sleep for a bit so that the message is easy to see.
      sleep 10
      echo "Hello, World!"

  services:
    enable:
    - myservice

  2. Run Image Customizer to create the LiveOS ISO file:

     sudo ./imagecustomizer \
   --build-dir ./build \
   --image-file <base-image.vhdx> \
   --output-image-file ./out/image.iso \
   --output-image-format iso \
   --config-file config.yaml

    Where:

    • <base-image.vhdx>: An official Azure Linux vhdx image file.

Run LiveOS ISO in Hyper-V

  1. Create VM:

    New-VM -Name mytestvm `
  -MemoryStartupBytes 2GB `
  -Generation 2 `
  -BootDevice CD `
  -NoVHD `
  -SwitchName "Default Switch"
Set-VMDvdDrive -VMName mytestvm -Path '<image.iso>'
Set-VMFirmware -VMName mytestvm -SecureBootTemplate MicrosoftUEFICertificateAuthority

    Where:

    • <image.iso>: Is the path of the ISO file that you generated with Image Customizer.

  2. Start VM:

    Start-VM -VMName mytestvm

Run LiveOS ISO in libvirt/QEMU

  1. Create and run VM:

    sudo virt-install \
  --name mytestvm \
  --import \
  --hvm \
  --machine q35 \
  --boot uefi \
  --os-variant linux2024 \
  --disk "<image.iso>,device=cdrom"

    Where:

    • <image.iso>: Is the path of the ISO file that you generated with Image Customizer.

      Note: It is sometimes necessary to move the ISO file out of your home directory to avoid permissions issues.