I'm thinking the opposite on this one. I think that your looking for bigger problems not keeping them around each other. At this point your dog is not showing aggression and if it was me I would want to keep it that way, which would mean letting the dog around it with supervision. My thought process being that if the rabbit ever gets out in accident you have less to worry about if your dog is already used to it and not looking at it like dinner. I've had pet rabbits and they would sleep with the dogs and cats. It would be no different if it was a kitten, if it was a kitten the question would be how do I get them to get along, you are one step ahead already. I'm not saying they need to be best friends, but for safety of the bunny, the dog needs to know the rabbit belongs.
Misty- Samoyed Mix, Tannor- Golden Retriever CGC
Robyn- GSD CGC, TC, Midnite-GSD CGC,TC, Brennan-Golden Retriever CGC, Batman-Husky/Greyhound , Apollo-GSD