Each resource must be configured in a resource group. The RGM brings all resources in a group online and offline together on the same node. When the RGM brings a resource group online or offline, it invokes callback methods on the individual resources in the group.
The nodes on which a resource group is currently online are called its primaries or primary nodes. A resource group is mastered by each of its primaries. Each resource group has an associated Nodelist property, set by the cluster administrator, which identifies all potential primaries or masters of the resource group.
A resource group also has a set of properties. These properties include configuration properties that can be set by the cluster administrator and dynamic properties, set by the RGM, that reflect the active state of the resource group.
The RGM defines two types of resource groups, failover and scalable. A failover resource group can be online on one node only at any time while a scalable resource group can be online on multiple nodes simultaneously. The RGM provides a set of properties to support the creation of each type of resource group. See Implementing a Failover Resource and Implementing a Scalable Resource for details on these properties.
See Table A–3 for a list of resource group properties.