Maybe nobody told August Alsina that the concert he was performing at was promoting 'Non-Violence', because getting into a fight backstage seems like a conflict of interests.

The show happened last weekend in St. Louis, and featured Alsina, Fabolous, and a host of others on stage.

Things started to go bad when August showed up late for the show, and was confronted by the promoter, Slim.  The video catches the two men, and their crews, exchanging words backstage.  Suddenly, they decide that talking about the issue isn't getting the job done, and punches start flying.

The best part is that Fab just sits back in the corner, drinking his drink, watching the madness take place.

If you're worried about the two men, don't.  Slip, the promoter, posted an Instagram video to show everyone that he's just fine.

The only way that this fight could have been better is if Fab would have jumped in to break it up with a shovel.