Enabling or preventing resources to start outside VCS control


Enabling or preventing resources to start outside VCS control
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When a resource is brought online on one node in a cluster, the resource must not be allowed to come online outside VCS control on any other node in the cluster. By ensuring that the resource cannot be online on more than one node, you can prevent data corruption and ensure high availability through VCS.

The ProPCV attribute of the service group containing application resource determines whether or not to allow the processes for the application resource to start outside VCS control. The application type resource must be registered with IMF for offline monitoring or online monitoring. ProPCV applies only to the processes that are specified in the MonitorProcesses attribute or the StartProgram attribute of the application type resource. See the Cluster Server Bundled Agents Reference Guide for information about the propcv action agent function and also for information on when the application resource can be registered with IMF for offline monitoring.

Note:

Currently, ProPCV works for application type resources only.

In situations where the propcv action agent function times out, you can use the amfregister command to manually mark a resource as one of the following:

A resource that is allowed to be brought online outside VCS control.
A resource that is prevented from being brought online outside VCS control. Such a ProPCV-enabled resource cannot be online on more than one node in the cluster.

To allow a resource to be started outside VCS control

Type the following command:
```
amfregister -r reapername -g resourcename -P a
```
Example: amfregister -r VCSApplicationAgent -g app1 -P a

The application resource app1 is allowed to start if you invoke it outside VCS control or from the command line.

To prevent a resource from being started outside VCS control

Type the following command:
```
amfregister -r reapername ‐g resourcename ‐P p
```
Example: amfregister -r VCSApplicationAgent -g app1 -P p

The application resource app1 is prevented from starting if you invoke it outside VCS control or from the command line.

In the preceding examples,

reapername is the agent whose name is displayed under the Registered Reapers section of amfstat output. For application resources, reapername is VCSApplicationAgent.
Option r indicates the name of the reaper or agent as displayed under the Registered Reapers section of the amfstat command's output. For application resources, reaper name is VCSApplicationAgent.
resourcename is the resource name.
Option g indicates the name of the resource. In the preceding example, the application resource is app1.
Option P indicates whether to allow or prevent a resource from starting up outside VCS control.
- Argument a denotes that the resource can be started outside VCS control.
- Argument p denotes that the resource is prevented from starting outside VCS control.