Rhodesian Ridgeback, though the photos you see of them are what the purebred looks like, there seems to be variations, because I had one purebred, (would have to find and scan the photo then post it so you could see) that was built like a rottweiler, much larger, he also had the white on his chest and legs, which the purists don't like, but to heck with them, this guy was just beautiful to look at, and mostly laid back unless another dog or stranger came by. I'm not sure what the whole deal is with the variations in their physique, but years ago we had a litter of them like this and kept this one, he might have been an anomaly, but their temperment is good, kind of loyal to one person, depends on how you raise and train them, they are friendly, but not overly aggressive. This guy liked to play right to the end of his life, I used to work out of town all week, he did well with a self feeder bin and auto watering dish, but when I was home I always treated him to a nice warm meal.
Real intelligent, excellent nose, this guy had a dog door on the garage door, never on a leash, he would stay by the house, often times hidden in the shrubs, had a nice place to lay down under the overhang, even on cold winter nights, he would be out there, watching the place, they seem to know who belongs and who does not. They will stand their ground, all of the ones we had were good all around. We did have one that was a little aggressive, and a little mean sometimes, his upbringing was not like it should have been though, none of the others were like that, he was just a little more protective at times, but still a great dog.
They seem to be active at night, a good friend in western NY has kept several at his place for 40+ years, you don't want to poke around there at night if they don't know you.