A heartbeat system and method is provided for a cluster system. In one embodiment, a heartbeat mechanism includes a quorum file for receiving heartbeat messages from the plurality of nodes. A network controller connects the quorum file to the plurality of nodes with a serial bus that establishes peer-to-peer and point-to-point device communication. A node map maintained by the network controller identifies active nodes based on signals from the serial bus. A status logic for determining a status of a node from the plurality of nodes by comparing heartbeat messages in the quorum file written by the node and the node map.