sorry, a bit of what you said is confusing.
if it is sucking the pedal to the floor, then the brakes should be locked on.
but you said no brakes unless you unplug the booster.

do you mean no pedal instead?

there is an internal valve that goes bad causing the vacuum to apply the brakes.

since there is still a physical connection you could just plug the vacuum line to the booster, but pedal effort will be very hard compared to with boost.