Preheat over to 325 F
Score the ham in a diamond pattern, about 1/8" deep.
Place pineapple rings evenly around the ham. Use the cloves to fix them to the ham.
Place ham in a large roasting pan on a rack.
Bake covered (or in a foil tent) for about 2 hours.
In a medium sauce pan, whisk together the pineapple juice, brown sugar, mustard, and vinegar.
Heat over medium stirring often, until the liquid has reduced a bit and thickens up. This should take about 15 minutes.
Uncover the ham and baste with the liquid.
Cook for another 30 minutes, basting a few more times while it cooks.
Remove from oven and let it rest for about 15 minutes before carving.