The 30 mm 12 point nut? I assume that you don't have a 1/2" drive impact gun? The parking brake will never hold it! If so you will need to use a couple wheel bolts screwed into the hub and a piece of pipe or something similar to brace the hub from turning. Break out or bend out the collar of the nut from the cut on the axle stub, to allow it to turn easier. Then you can use a large breaker bar possibly a pipe extension on that! In my experience the best thing to do is to heat the nut too hot to touch with a propane torch and then while it is still hot put the tool to it, keep the tool straight and square to the nut and put your weight to it.

The working surface of the nut is pretty thin so if you have a socket with significant radius at its opening you can grind off that radius to allow more of the tool working surface to make more and better contact with the nut's surfaces.