shutdowncommand

type ShutdownConfig struct {
	// The command to use to gracefully shut down the machine once all
	// provisioning is complete. By default this is an empty string, which
	// tells Packer to just forcefully shut down the machine. This setting can
	// be safely omitted if for example, a shutdown command to gracefully halt
	// the machine is configured inside a provisioning script. If one or more
	// scripts require a reboot it is suggested to leave this blank (since
	// reboots may fail) and instead specify the final shutdown command in your
	// last script.
	ShutdownCommand string `mapstructure:"shutdown_command" required:"false"`
	// The amount of time to wait after executing the shutdown_command for the
	// virtual machine to actually shut down. If the machine doesn't shut down
	// in this time it is considered an error. By default, the time out is "5m"
	// (five minutes).
	ShutdownTimeout time.Duration `mapstructure:"shutdown_timeout" required:"false"`
}