1. An apparatus for managing failover in a clustered system, the clustered system comprising a plurality of sub-clusters connected with one another by a first set of links, each sub-cluster comprising a plurality of nodes connected with one another by a second set of links, the apparatus comprising: a determination unit configured to determine, by using at least one of the second set of links, that a suspect node within a same sub-cluster has stopped; and a notification unit configured to, in response to the determination, transmit a lease relinquish message on behalf of the suspect node.