1. A method comprising: determining a system status including a system-level bit masked word having a plurality of bits, each bit corresponding to a status of a different hierarchical level of the system, wherein determining the system status includes determining an entity status for one or more entities; receiving one or more updated entity status words from an entity at a lower hierarchy level, wherein the one or more updated entity status words are received as part of a heartbeat signal from the entity at the lower hierarchy level; querying one or more entities in successively lower hierarchy levels so long as a cascaded state change is identified for a corresponding entity in a lower hierarchy level; and determining the current status for one or more entities having a changed status, wherein identifying a cascaded state change includes performing a logical exclusive OR operation on a previous status bit masked word and a current status bit masked word of an entity.