Resources
A cluster resource is any physical or logical component that has the following characteristics.
- It can be brought online and taken offline.
- It can be managed in a cluster.
- It can be hosted (owned) by only one node at a time.
To manage resources, the Cluster service communicates to a resource DLL through a Resource Monitor. In response to a Cluster service request, the Resource Monitor calls the appropriate entry-point function in the resource DLL to check and control the resource's state.
A resource can specify one or more resources on which it is dependent. A dependent resource is one that requires another resource to operate. For example, a network name won't work by itself; it must be associated with an IP address. Because of this requirement, a Network Name resource is dependent on an IP Address resource. Dependent resources are taken offline before the resources upon which they depend are taken offline, and they are brought online after these resources are brought online.
A resource can also specify a list of nodes on which it is able to run. Preferred nodes and dependencies are important considerations when administrators organize resources into groups.
[!Important]
In Windows Server 2012, a resource can be placed in locked mode, which is maintained in the volatile cluster state.
The following topics describe important concepts related to resources:
Resource concepts | Description |
---|---|
Quorum Resource | Describes the fundamental role it plays in defining the cluster. |
Resource Failure | Describes how the Cluster service determines when a resource has failed, as well as ways for developers and administrators to adjust that process. |
Resource Dependencies | Provides information on the effects of dependency relationships between resources, and lists the required dependencies of the default resource types. |
For more information on working with resources, see the following topics.
- Resource Common Properties
- Resource Control Codes
- Resource Management Functions
- Resource DLL Entry Point Functions
- Resource DLL Callback Functions