Oracle Clusterware manages resources based on how you configure them to increase their availability. You can configure your resources so that Oracle Clusterware:
Starts resources during cluster or server start
Restarts resources when failures occur
Relocates resources to other servers, if the servers are available
To manage your applications with Oracle Clusterware:
Use the generic_application resource type, write a custom script for the script agent, or develop a new agent.
Register your applications as resources with Oracle Clusterware.
If a single application requires that you register multiple resources, you may be required to define relevant dependencies between the resources.
Assign the appropriate privileges to the resource.
Start or stop your resources.
When a resource fails, Oracle Clusterware attempts to restart the resource based on attribute values that you provide when you register an application or process as a resource. If a server in a cluster fails, then you can configure your resources so that processes that were assigned to run on the failed server restart on another server. Based on various resource attributes, Oracle Clusterware supports a variety of configurable scenarios.
When you register a resource in Oracle Clusterware, the relevant information about the application and the resource-relevant information, is stored in the Oracle Cluster Registry (OCR). This information includes:
Path to the action script or application-specific agent: This is the absolute path to the script or application-specific agent that defines the start, stop, check, and clean actions that Oracle Clusterware performs on the application.
See Also:
"Agents in Oracle Clusterware" for more information about these actions
Privileges: Oracle Clusterware has the necessary privileges to control all of the components of your application for high availability operations, including the right to start processes that are owned by other user identities. Oracle Clusterware must run as a privileged user to control applications with the correct start and stop processes.
Resource Dependencies: You can create relationships among resources that imply an operational ordering or that affect the placement of resources on servers in the cluster. For example, Oracle Clusterware can only start a resource that has a hard start dependency on another resource if the other resource is running. Oracle Clusterware prevents stopping a resource if other resources that depend on it are running. However, you can force a resource to stop using the crsctl stop resource -f command, which first stops all resources that depend on the resource being stopped.
This section includes the following topics: