Cluster Resource States

Resource States

Every resource in a cluster is in a particular state at any time. Certain actions or events can cause that state to change.

ONLINE The resource is running.

OFFLINE The resource is not running.

UNKNOWN An attempt to stop the resource has failed. Oracle Clusterware does not actively monitor resources that are in this state. 

You must perform an application-specific action to ensure that the resource is offline, such as stop a process, and then run the crsctl stop resource command to reset the state of the resource to OFFLINE.

INTERMEDIATE A resource can be in the INTERMEDIATE state because of one of two events:

1. Oracle Clusterware cannot determine the state of the resource but the resource was either attempting to go online or was online the last time its state was precisely known. 

Usually, the resource transitions out of this state on its own over time, as the conditions that impeded the check action no longer apply.

2. A resource is partially online. For example, the Oracle Database VIP resource fails over to another server when its home server leaves the cluster. 

However, applications cannot use this VIP to access the database while it is on a non-home server. 

Similarly, when an Oracle Database instance is started and not open, the resource is partially online: it is running but is not available to provide services.

Oracle Clusterware actively monitors resources that are in the INTERMEDIATE state and, typically, you are not required to intervene. 

If the resource is in the INTERMEDIATE state due to the preceding reason 1, then as soon as the state of the resource is established, Oracle Clusterware transitions the resource out of the INTERMEDIATE state.

If the resource is in the INTERMEDIATE state due to the preceding reason 2, then it stays in this state if it remains partially online. 

For example, the home server of the VIP must rejoin the cluster so the VIP can switch over to it. A database administrator must issue a command to open the database instance.

In either case, however, Oracle Clusterware transitions the resource out of the INTERMEDIATE state automatically as soon as it is appropriate.Use the STATE_DETAILS resource attribute to explain the reason for a resource being in the INTERMEDIATE state and provide a solution to transition the resource out of this state.

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