Keep him on leash, and have them completely ignore him. Let him move at his own pace, don't force him to greet anyone if he doesn't want to.
My dogs STILL bark when people come over because it doesn't happen frequently enough for it to be a routine experience for them, but they always settle down after a bit. So I keep them on leash until they're calm, often with a bully stick or stuffed Kong to work on, or I'll just have them do a "down" and "watch" for treats until everyone is inside and sitting down. Then I'll drop the leashes, and once I'm sure that they're not going to jump all over everyone we take the leashes off and they're fine.