proxmox image cloud-init

cloud-init.sh

#!/usr/bin/env bash
set -Eeuo pipefail

if [[ "${DEBUG:-0}" == "1" ]]; then
  set -x
fi

VMID="${VMID:-9001}"
STORAGE="${STORAGE:-local-lvm}"
RELEASE="${RELEASE:-noble}"
IMAGE_SIZE="${IMAGE_SIZE:-32G}"
IMAGE_DIR="${IMAGE_DIR:-/var/lib/vz/template/iso}"
SNIPPET_DIR="${SNIPPET_DIR:-/var/lib/vz/snippets}"
SNIPPET_STORAGE="${SNIPPET_STORAGE:-local}"
SNIPPET_NAME="${SNIPPET_NAME:-ubuntu.yaml}"
SSH_KEY_FILE="${SSH_KEY_FILE:-./id_ed25519.pub}"
VM_NAME="${VM_NAME:-ubuntu-${RELEASE}-template}"
NET0="${NET0:-virtio,bridge=vmbr0,mtu=1}"
TAGS="${TAGS:-${RELEASE},cloudinit,ansible}"

IMAGE_TEMPLATE="${IMAGE_TEMPLATE:-${IMAGE_DIR}/${RELEASE}-server-cloudimg-amd64.img}"
IMAGE_URL="${IMAGE_URL:-https://cloud-images.ubuntu.com/${RELEASE}/current/${RELEASE}-server-cloudimg-amd64.img}"
SNIPPET_PATH="${SNIPPET_DIR}/${SNIPPET_NAME}"

require_command() {
  local command_name="$1"

  if ! command -v "$command_name" >/dev/null 2>&1; then
    echo "Missing required command: ${command_name}" >&2
    exit 1
  fi
}

require_file() {
  local file_path="$1"
  local description="$2"

  if [[ ! -f "$file_path" ]]; then
    echo "Missing ${description}: ${file_path}" >&2
    exit 1
  fi
}

download_file() {
  local source_url="$1"
  local destination_path="$2"

  if command -v curl >/dev/null 2>&1; then
    curl -fL --retry 3 -o "$destination_path" "$source_url"
    return
  fi

  if command -v wget >/dev/null 2>&1; then
    wget -O "$destination_path" "$source_url"
    return
  fi

  echo "Missing required command: curl or wget" >&2
  exit 1
}

ensure_cloud_image() {
  if [[ -f "$IMAGE_TEMPLATE" ]]; then
    return
  fi

  local partial_image="${IMAGE_TEMPLATE}.part"

  echo "Cloud image not found: ${IMAGE_TEMPLATE}" >&2
  echo "Downloading cloud image from: ${IMAGE_URL}" >&2

  mkdir -p "$IMAGE_DIR"
  rm -f "$partial_image"
  download_file "$IMAGE_URL" "$partial_image"
  mv "$partial_image" "$IMAGE_TEMPLATE"
}

prompt_for_username() {
  local username

  read -r -p "Username: " username
  if [[ -z "$username" ]]; then
    echo "Username is required." >&2
    exit 1
  fi

  printf '%s' "$username"
}

prompt_for_password() {
  if [[ -n "${CLEARTEXT_PASSWORD:-}" ]]; then
    printf '%s' "$CLEARTEXT_PASSWORD"
    return
  fi

  local password

  read -r -s -p "Password: " password
  printf '\n' >&2

  if [[ -z "$password" ]]; then
    echo "Password is required." >&2
    exit 1
  fi

  printf '%s' "$password"
}

apt_sources_file() {
  if [[ "$RELEASE" == "noble" ]]; then
    printf '%s' "/etc/apt/sources.list.d/ubuntu.sources"
  else
    printf '%s' "/etc/apt/sources.list"
  fi
}

write_cloud_init_snippet() {
  local sources_file

  sources_file="$(apt_sources_file)"
  mkdir -p "$SNIPPET_DIR"

  cat > "$SNIPPET_PATH" <<EOF
#cloud-config
runcmd:
  - sed -i 's/archive.ubuntu.com/mirror.kku.ac.th/g' ${sources_file}
  - sed -i 's/security.ubuntu.com/mirror.kku.ac.th/g' ${sources_file}
  - echo 'Acquire::ForceIPv4 "true";' > /etc/apt/apt.conf.d/99force-ipv4
  - apt-get update -y
  - apt-get upgrade -y
  - apt-get install -y qemu-guest-agent
  - apt-get install -y bash-completion
  - systemctl enable ssh
  - reboot
# Taken from https://forum.proxmox.com/threads/combining-custom-cloud-init-with-auto-generated.59008/page-3#post-428772
EOF
}

create_vm() {
  local username="$1"
  local password_hash="$2"

  qemu-img resize "$IMAGE_TEMPLATE" "$IMAGE_SIZE"

  qm create "$VMID" --name "$VM_NAME" \
    --memory 8192 --balloon 0 \
    --agent 1 \
    --sockets 2 \
    --cores 2 \
    --net0 "$NET0" \
    --scsihw virtio-scsi-pci

  qm set "$VMID" --scsi0 "${STORAGE}:0,import-from=${IMAGE_TEMPLATE},ssd=1"
  qm set "$VMID" --boot order=scsi0
  qm set "$VMID" --ide2 "${STORAGE}:cloudinit"
  qm set "$VMID" --cicustom "vendor=${SNIPPET_STORAGE}:snippets/${SNIPPET_NAME}"
  qm set "$VMID" --tags "$TAGS"
  qm set "$VMID" --ciupgrade 0
  qm set "$VMID" --ciuser "$username"
  qm set "$VMID" --cipassword "$password_hash"
  qm set "$VMID" --sshkeys "$SSH_KEY_FILE"
  qm set "$VMID" --ipconfig0 ip=dhcp

  qm template "$VMID"
}

main() {
  require_command openssl
  require_command qm
  require_command qemu-img
  ensure_cloud_image
  require_file "$SSH_KEY_FILE" "SSH public key"

  local username
  local password
  local password_hash

  username="$(prompt_for_username)"
  password="$(prompt_for_password)"
  password_hash="$(openssl passwd -6 "$password")"

  write_cloud_init_snippet
  create_vm "$username" "$password_hash"
}

main "$@"