clone-and-provision

#!/bin/bash
#
# Code example: clone a template, add an extra data disk, and provision guest
# credentials + disk mount behavior with cloud-init user-data.

set -euo pipefail

TEMPLATE_ID=${TEMPLATE_ID:-"9000"}
VM_ID=${VM_ID:-"9100"}
VM_NAME=${VM_NAME:-"cloned-vm"}
FULL_CLONE=${FULL_CLONE:-"false"}

EXTRA_DATASTORE=${EXTRA_DATASTORE:-"local-lvm"}
EXTRA_SIZE=${EXTRA_SIZE:-"16G"}
EXTRA_MOUNTPOINT=${EXTRA_MOUNTPOINT:-"/home/jack"}
EXTRA_FSTYPE=${EXTRA_FSTYPE:-"xfs"}
NET_VLAN=${NET_VLAN:-"null"}
NET_BRIDGE=${NET_BRIDGE:-""}

CI_USER=${CI_USER:-"jack"}
CI_PASSWORD_HASH=${CI_PASSWORD_HASH:-""}
SSH_PUBKEY_FILE=${SSH_PUBKEY_FILE:-"$HOME/.ssh/id_rsa.pub"}

function err() {
  echo "Error: $*" >&2
  exit 2
}

function usage() {
  cat >&2 <<'EOF'
Usage: clone-and-provision --template-id <ID> --id <VM_ID> --name <VM_NAME> [ARGS]

Required:
  --template-id <ID>         Source template ID, e.g. 9000
  --id <VM_ID>               New VM ID
  --name <VM_NAME>           New VM name
  --ci-password-hash <HASH>  SHA-512 hash from: openssl passwd -6

Optional:
  --full-clone <true|false>  Full clone (default: false, linked clone)
  --datastore <NAME>         Extra disk datastore (default: local-lvm)
  --size <SIZE>              Extra disk size, GiB/TiB only (default: 16G)
  --mountpoint <PATH>        Mount point in guest (default: /home/jack)
  --fstype <ext4|xfs>        Filesystem for extra disk (default: xfs)
  --net-bridge <BRIDGE>      Network bridge for net0, e.g. vmbr0
  --net-vlan <ID|null>       VLAN tag for net0, null removes tag (default: null)
  --ci-user <NAME>           Cloud-init username (default: jack)
  --ssh-pubkey-file <PATH>   Public key file (default: ~/.ssh/id_rsa.pub)

Example:
  clone-and-provision \
    --template-id 9000 --id 9101 --name db-vm01 \
    --datastore local-lvm --size 16G \
    --mountpoint /home/jack --fstype xfs \
    --net-bridge vmbr0 \
    --net-vlan null \
    --ci-user jack --ssh-pubkey-file /root/.ssh/id_ed25519.pub \
    --ci-password-hash '$6$...'
EOF
  exit 2
}

while [[ $# -gt 0 ]]; do
  case "$1" in
  --help|-h)
    usage
    ;;
  --template-id)
    [[ $# -lt 2 || "$2" == -* ]] && err "Missing argument for $1"
    TEMPLATE_ID=$2
    shift 2
    ;;
  --id)
    [[ $# -lt 2 || "$2" == -* ]] && err "Missing argument for $1"
    VM_ID=$2
    shift 2
    ;;
  --name)
    [[ $# -lt 2 || "$2" == -* ]] && err "Missing argument for $1"
    VM_NAME=$2
    shift 2
    ;;
  --full-clone)
    [[ $# -lt 2 || "$2" == -* ]] && err "Missing argument for $1"
    FULL_CLONE=$2
    shift 2
    ;;
  --datastore)
    [[ $# -lt 2 || "$2" == -* ]] && err "Missing argument for $1"
    EXTRA_DATASTORE=$2
    shift 2
    ;;
  --size)
    [[ $# -lt 2 || "$2" == -* ]] && err "Missing argument for $1"
    EXTRA_SIZE=$2
    shift 2
    ;;
  --mountpoint)
    [[ $# -lt 2 || "$2" == -* ]] && err "Missing argument for $1"
    EXTRA_MOUNTPOINT=$2
    shift 2
    ;;
  --fstype)
    [[ $# -lt 2 || "$2" == -* ]] && err "Missing argument for $1"
    EXTRA_FSTYPE=$2
    shift 2
    ;;
  --net-bridge)
    [[ $# -lt 2 || "$2" == -* ]] && err "Missing argument for $1"
    NET_BRIDGE=$2
    shift 2
    ;;
  --net-vlan)
    [[ $# -lt 2 || "$2" == -* ]] && err "Missing argument for $1"
    NET_VLAN=$2
    shift 2
    ;;
  --ci-user)
    [[ $# -lt 2 || "$2" == -* ]] && err "Missing argument for $1"
    CI_USER=$2
    shift 2
    ;;
  --ci-password-hash)
    [[ $# -lt 2 || "$2" == -* ]] && err "Missing argument for $1"
    CI_PASSWORD_HASH=$2
    shift 2
    ;;
  --ssh-pubkey-file)
    [[ $# -lt 2 || "$2" == -* ]] && err "Missing argument for $1"
    SSH_PUBKEY_FILE=$2
    shift 2
    ;;
  -* )
    err "Unknown Argument: $1"
    ;;
  *)
    err "Unexpected positional argument: $1"
    ;;
  esac
done

[[ -z "${TEMPLATE_ID}" ]] && err "Missing --template-id"
[[ -z "${VM_ID}" ]] && err "Missing --id"
[[ -z "${VM_NAME}" ]] && err "Missing --name"
[[ -z "${CI_PASSWORD_HASH}" ]] && err "Missing --ci-password-hash"
[[ -r "${SSH_PUBKEY_FILE}" ]] || err "Cannot read SSH pubkey file: ${SSH_PUBKEY_FILE}"

if [[ "${EXTRA_FSTYPE}" != "xfs" && "${EXTRA_FSTYPE}" != "ext4" ]]; then
  err "--fstype must be xfs or ext4"
fi

if [[ "${FULL_CLONE}" != "true" && "${FULL_CLONE}" != "false" ]]; then
  err "--full-clone must be true or false"
fi

if [[ ! "${EXTRA_SIZE}" =~ ^[0-9]+[GgTt]$ ]]; then
  err "--size must be in GiB/TiB (for example: 16G, 1T)"
fi

if [[ "${NET_VLAN}" != "null" && ! "${NET_VLAN}" =~ ^[0-9]{1,4}$ ]]; then
  err "--net-vlan must be null or a numeric VLAN ID"
fi

if ! command -v qm >/dev/null 2>&1; then
  err "qm command not found"
fi

if ! qm status "${TEMPLATE_ID}" >/dev/null 2>&1; then
  err "Template VM ID not found: ${TEMPLATE_ID}"
fi

if qm status "${VM_ID}" >/dev/null 2>&1; then
  err "Target VM ID already exists: ${VM_ID}"
fi

ssh_key=$(<"${SSH_PUBKEY_FILE}")
snippet_file="/var/lib/vz/snippets/${VM_NAME}-user-data.yaml"
snippet_name="${VM_NAME}-user-data.yaml"
disk_serial="data${VM_ID}"
disk_by_id="/dev/disk/by-id/virtio-${disk_serial}"

echo "Template ID:        ${TEMPLATE_ID}"
echo "Target VM ID:       ${VM_ID}"
echo "Target VM Name:     ${VM_NAME}"
echo "Full Clone:         ${FULL_CLONE}"
echo "Extra Datastore:    ${EXTRA_DATASTORE}"
echo "Extra Disk Size:    ${EXTRA_SIZE}"
echo "Extra Filesystem:   ${EXTRA_FSTYPE}"
echo "Extra Mount Point:  ${EXTRA_MOUNTPOINT}"
echo "Network Bridge:     ${NET_BRIDGE:-inherit}"
echo "Network VLAN:       ${NET_VLAN}"
echo "Cloud-init User:    ${CI_USER}"
echo "Cloud-init Snippet: ${snippet_file}"

if [[ ! -d /var/lib/vz/snippets ]]; then
  err "/var/lib/vz/snippets directory is missing, enable snippets storage"
fi

cat >"${snippet_file}" <<EOF
#cloud-config
users:
  - default
  - name: ${CI_USER}
    groups: [sudo]
    shell: /bin/bash
    sudo: ALL=(ALL) NOPASSWD:ALL
    lock_passwd: false
    passwd: ${CI_PASSWORD_HASH}
    ssh_authorized_keys:
      - ${ssh_key}

package_update: true
packages:
  - qemu-guest-agent

write_files:
  - path: /usr/local/sbin/provision-extra-disk.sh
    permissions: "0755"
    owner: root:root
    content: |
      #!/usr/bin/env bash
      set -euo pipefail
      DEVICE="${disk_by_id}"
      FSTYPE="${EXTRA_FSTYPE}"
      MOUNTPOINT="${EXTRA_MOUNTPOINT}"
      MARKER="/var/lib/cloud/instance/extra-disk.done"

      [[ -f "\$MARKER" ]] && exit 0
      [[ -b "\$DEVICE" ]] || exit 0

      if ! blkid "\$DEVICE" >/dev/null 2>&1; then
        if [[ "\$FSTYPE" == "xfs" ]]; then
          if ! command -v mkfs.xfs >/dev/null 2>&1; then
            apt-get update
            apt-get install -y xfsprogs
          fi
          mkfs.xfs -f "\$DEVICE"
        else
          mkfs.ext4 -F "\$DEVICE"
        fi
      fi

      mkdir -p "\$MOUNTPOINT"
      UUID=\$(blkid -s UUID -o value "\$DEVICE")
      grep -q "UUID=\$UUID" /etc/fstab || echo "UUID=\$UUID \$MOUNTPOINT \$FSTYPE defaults,nofail 0 2" >> /etc/fstab
      mount -a

      touch "\$MARKER"

runcmd:
  - [bash, -lc, "/usr/local/sbin/provision-extra-disk.sh"]
EOF

echo "Cloning template..."
if [[ "${FULL_CLONE}" == "true" ]]; then
  qm clone "${TEMPLATE_ID}" "${VM_ID}" --name "${VM_NAME}" --full true
else
  qm clone "${TEMPLATE_ID}" "${VM_ID}" --name "${VM_NAME}" --full false
fi

echo "Configuring network VLAN..."
current_net0=$(qm config "${VM_ID}" | awk -F': ' '/^net0:/{print $2; exit}')
[[ -z "${current_net0}" ]] && err "Missing net0 config on cloned VM"

if [[ "${NET_VLAN}" == "null" ]]; then
  updated_net0=$(echo "${current_net0}" | sed -E 's/,?tag=[0-9]+//g' | sed -E 's/,,+/,/g; s/^,|,$//g')
else
  if echo "${current_net0}" | grep -q 'tag='; then
    updated_net0=$(echo "${current_net0}" | sed -E "s/tag=[0-9]+/tag=${NET_VLAN}/")
  else
    updated_net0="${current_net0},tag=${NET_VLAN}"
  fi
fi

if [[ -n "${NET_BRIDGE}" ]]; then
  if echo "${updated_net0}" | grep -q 'bridge='; then
    updated_net0=$(echo "${updated_net0}" | sed -E "s/bridge=[^,]+/bridge=${NET_BRIDGE}/")
  else
    updated_net0="${updated_net0},bridge=${NET_BRIDGE}"
  fi
fi

qm set "${VM_ID}" --net0 "${updated_net0}"

echo "Adding extra disk..."
primary_disk_spec="${EXTRA_DATASTORE}:${EXTRA_SIZE},discard=on,serial=${disk_serial}"
if ! disk_add_error=$(qm set "${VM_ID}" --virtio1 "${primary_disk_spec}" 2>&1); then
  # dir-backed storage (for example "local") cannot allocate from <storage>:<size> on this path.
  # Create the volume first, then attach the created volid.
  if echo "${disk_add_error}" | grep -qi "unable to parse directory volume name"; then
    echo "Primary disk syntax failed for ${EXTRA_DATASTORE}; creating disk volume, then attaching..."
    if ! qm disk create "${VM_ID}" "${EXTRA_DATASTORE}" --size "${EXTRA_SIZE}" --format qcow2 >/dev/null 2>&1; then
      if [[ "${EXTRA_DATASTORE}" == "local" ]]; then
        command -v qemu-img >/dev/null 2>&1 || err "qemu-img is required for local directory fallback"
        local_images_dir="/var/lib/vz/images/${VM_ID}"
        local_disk_file="${local_images_dir}/vm-${VM_ID}-disk-extra.qcow2"
        mkdir -p "${local_images_dir}"
        qemu-img create -f qcow2 "${local_disk_file}" "${EXTRA_SIZE}" >/dev/null
        qm disk rescan --vmid "${VM_ID}" >/dev/null
      else
        err "Automatic fallback could not create disk on datastore '${EXTRA_DATASTORE}'. On this Proxmox version, use --datastore local or create/attach the disk manually."
      fi
    fi
    created_extra_disk=$(qm config "${VM_ID}" | awk -F': ' '/^unused[0-9]+:/{v=$2} END{print v}')
    [[ -z "${created_extra_disk}" ]] && err "Failed to discover created extra disk volume"
    qm set "${VM_ID}" --virtio1 "${created_extra_disk},discard=on,serial=${disk_serial}"
  else
    err "Failed adding extra disk: ${disk_add_error}"
  fi
fi

echo "Applying cloud-init user-data snippet..."
qm set "${VM_ID}" --cicustom "user=local:snippets/${snippet_name}"

echo "Done. Start VM with: qm start ${VM_ID}"