This is due to the configuration on Amazon.
- Open Amazon EC2 console
- Click ‘Instances’ on the navigation pane and the appropriate instance
- Click ‘Actions’ and select ‘Instance Settings’
- Click ‘Change Shutdown Behavior’
- For Barracuda WAF instance select the ‘Shutdown behavior’ as stop
When the shutdown behavior is set as ‘Terminate’ the WAF instance will get terminated when a shutdown/hardreboot is performed.