Means absolutely fuming, like you’re one minor inconvenience away from writing an email to the universe. But it can also mean something is class or the craic is flying, especially when you’re talking about a night out. Same word, opposite moods, so you’ve got to read the room or you’ll sound like a gobshite.
"I was raging when the bus sailed on, but later in the pub the craic was raging, pints flowing, DJ blaring, everyone skitting."