Example `init.d` script for hooking into the system shutdown

cloud-init

#cloud-config

write_files:
  - path: /etc/init.d/on-shutdown
    owner: root:root
    permissions: '0755'
    content: |
      #!/bin/sh
      #
      # /etc/init.d/on-shutdown
      #
      # chkconfig: 12345 95 02
      # description: Execute on shutdown
      #
      ### BEGIN INIT INFO
      # Provides: on-shutdown
      # Required-Start: $local_fs
      # Default-Start: 1 2 3 4 5
      # Default-Stop:  0 6
      # Short-Description: Execute script on system shutdown
      ### END INIT INFO
      . /etc/init.d/functions
      EXEC_NAME=on-shutdown
      LOCK_FILE=/var/lock/subsys/$EXEC_NAME
      LOG_FILE=/var/log/on-shutdown.log
      RET_VAL=0
      start() {
        touch $LOCK_FILE
        touch $LOG_FILE
        echo
      }
      stop() {
        echo 'Stopping on-shutdown' >> $LOG_FILE
        rm -rf $LOCK_FILE
        echo
      }
      case "$1" in
        start)
          start
          ;;
        stop)
          stop
          ;;
        *)
          echo $"Usage: $0 {start|stop}"
          ;;
      esac
      exit $RET_VAL

runcmd:
  - 'chkconfig --add on-shutdown && service on-shutdown start'

etc_init.d_on-shutdown

#!/bin/sh
#
# /etc/init.d/on-shutdown
#
# chkconfig: 12345 95 02
# description: Execute on shutdown
#
### BEGIN INIT INFO
# Provides: on-shutdown
# Required-Start: $local_fs
# Default-Start: 1 2 3 4 5
# Default-Stop:  0 6
# Short-Description: Execute script on system shutdown
### END INIT INFO
. /etc/init.d/functions
EXEC_NAME=on-shutdown
LOCK_FILE=/var/lock/subsys/$EXEC_NAME
LOG_FILE=/var/log/on-shutdown.log
RET_VAL=0
start() {
  touch $LOCK_FILE
  touch $LOG_FILE
  echo
}
stop() {
  echo 'Stopping on-shutdown' >> $LOG_FILE
  rm -rf $LOCK_FILE
  echo
}
case "$1" in
  start)
    start
    ;;
  stop)
    stop
    ;;
  *)
    echo $"Usage: $0 {start|stop}"
    ;;
esac
exit $RET_VAL