Patent ID: 7275100

Claim:
An apparatus for sending a heartbeat signal in a cluster computing system, the apparatus comprising: a first host group; and a first storage system comprising a first heartbeat storage volume and a first data storage volume, the first storage system being associated with the first host group, the first host group coupled via a network to a second host group, the first storage system coupled via a remote link separate from the network to a second storage system comprising a second heartbeat storage volume and a second data storage volume, the second storage system being associated with the second host group, the first host group configured to selectively send a heartbeat signal to the second host group by use of the remote link by sending a memory command to the first heartbeat storage volume of the first storage system which is mirrored via the remote link using a remote copy mechanism to the second heartbeat storage volume of the second storage system, wherein the second host group is configured to use the received heartbeat signal to determine whether a failover should be performed; and wherein: the first heartbeat storage volume and second heartbeat storage volume form a remote minor being in an enabled mode; the first heartbeat storage volume is registered to a device address entry; the first host group operable to send an activation message to the second host group; and the second heartbeat volume is registered to the device address entry.