All cards I have in the shelf here do provide the ability to operate in "software-watchdog" mode:
I.e. you configure them for startup, they go to "non-bypass-mode". The stay in that mode as long as the wathcdog trigger software does give the card a "I'm still alive" signal every few seconds (configurable). If this heartbeat is not getting to the card anymore (kernel panic, for example), the card will go to bypass mode automatically.
its would be an awesome feature with to work with some border mikrotiks that act as a traffic shaper like a (man in the middle betwen , Upstream provider and the border / core switch or router)