Issue
Usually, when you want to use the front power button on a Firebox to power it off, you must press and hold the power button for 5 seconds. On some Firebox M200 and Firebox M300 devices, when you press the front power button, it powers off immediately. This only affects specific hardware revisions:
Firebox M200: Rev HFirebox M300: Rev E
The hardware revision appears on a small sticker, to the right of the WatchGuard serial number sticker on the rear of the appliance.