1. A method of managing spare partition units in a partitionable computing device by a global management entity, the method comprising: determining if a spare partition unit is required for addition or replacement in a local operating system; and if a spare partition is required for addition, initiating an addition of a spare partition unit, else: (a) initiating a replacement of a failing partition unit with a spare partition unit; (b) passively migrating the spare partition unit into the failing partition unit's partition; (c) actively migrating the spare partition unit into the failing partition unit's partition; and (d) cleaning up the partitionable computing device.