Cluster computer system

A node in a cluster computer system comprising:

• a determination engine to determine that a second node in the cluster computer system has become unavailable;
• a formation engine to form a first sub-cluster with a plurality of nodes that are communicatively reachable in the cluster computer system;
• a retention engine to retain ownership over a first application running on the node, to the exclusion of remaining nodes in the first sub-cluster, wherein to retain ownership over the first application comprises controlling access to a storage volume related to the first application;
• and
• an application engine to:
• attempt to obtain ownership over a second application previously running on the second node before the second node became unavailable, wherein the attempt is parallel to an attempt by the remaining nodes in the first sub-cluster to obtain ownership over the second application;
• and
• in response to a successful attempt, obtain ownership over the second application, to the exclusion of the remaining nodes in the first sub-cluster, wherein to obtain ownership over the second application comprises controlling access to a storage volume related to the second application.

A non-transitory machine-readable storage medium comprising instructions, the instructions executable by a processor to:

• determine, by a first node in a cluster computer system, that a second node in the cluster computer system has become unavailable;
• form, by the first node, a first sub-cluster with a plurality of nodes that are communicatively reachable in the cluster computer system;
• retain, by the first node, ownership over a first application running on the first node, to the exclusion of remaining nodes in the first sub-cluster, wherein retaining ownership over the first application comprises controlling access to a storage volume related to the first application;
• attempt, by the first node, to obtain ownership over a second application previously running on the second node before the second node became unavailable;
• in response to a successful attempt, obtain, by the first node, ownership over the second application, to the exclusion of the remaining nodes in the first sub-cluster, wherein obtaining ownership over the second application comprises controlling access to a storage volume related to the second application;
• and
• identify the remaining nodes in the first sub-cluster as backup nodes for the first application, wherein one of the backup nodes to acquire ownership over the first application in case the node becomes unavailable.