Actually, I think he knocks on the house walls, not the door.
I wouldn’t shoot through the door, in any case (unless a bullet had already come in...). In any case, this is a looney prankster, not an attacker. I’d sit up with a shotgun so I’d have a forceful argument for a behavior change when I came out to discuss his activities. A shotgun gives you more options - you can shoot him if he’s dangerous, or butt-stroke him if he just needs something to focus his attention.
Come to think of it, I might be more scared of a mean dog than a guy with a gun... The guy with the gun might show some restraint. The dog won’t...
One big dog would take care of The Knocker. Yes. My sis has this huge dog, I don’t remember the breed, but when he barks it’s like The Hound of the Baskervilles! This guy would go from being ‘The Knocker’ to being ‘The Runner’.