Patent ID: 7555544

Claim:
A system comprising: a cluster having a plurality of nodes, wherein each of the plurality of nodes is a computer system comprising hardware and software configured to execute on the hardware, wherein the software is stored on the hardware, and wherein at least one of the nodes is a candidate node; a plurality of resource groups; a clustering mechanism executing on the cluster configured to activate a first resource group of the plurality of resource groups on the candidate node; and a resource group affinity of the plurality of resource groups, wherein the resource group affinity comprises: a unidirectional association between the first resource group of the plurality of resource groups and a second resource group of the plurality of resource groups, an affinity type for defining the resource group affinity of the first resource group to the second resource group, wherein the affinity type is one selected from a group consisting of a positive affinity type and a negative affinity type, wherein the positive affinity type indicates that the clustering mechanism should attempt to activate the first resource group on a same node as the second resource group, and wherein the negative affinity type indicates that the clustering mechanism should attempt to activate the first resource group on a different node than the second resource group, and an affinity strength defining a degree of the affinity type of the resource group affinity, wherein the affinity strength is one selected from the group consisting of a strong affinity strength, a weak affinity strength, and a mutual strong affinity strength.