Cluster administrative domain

A cluster administrative domain is used to manage resources that need to be maintained consistently across the nodes in a clustered environment.

There can be certain operational or configuration parameters that need to be defined on each node which is an access point for resilient data, applications, and devices. If a change is made to one of these parameters on any node that may be an access point for something, that change needs to propagated to all other nodes which can be a potential access point. A cluster administrative domain provides the capability to identify resources which need to be maintained consistently across the nodes in a domain. It then monitors for changes to these resources and synchronizes the changes across the active domain. A cluster administrative domain is represented by a peer CRG. When a cluster administrative domain is created, the peer CRG is created by the system. The name of the cluster administrative domain becomes the name of the peer CRG. The nodes which make up the cluster administrative domain are defined by the recovery domain of the peer CRG. All of the nodes are peer nodes. Replicate nodes are not allowed in a cluster administrative domain. A cluster node can only be defined in one cluster administrative domain within the cluster. For more information on associated cluster administrative domain tasks, see the following topics:

Once the cluster administrative domain is created, normal CRG functions are used to manage the cluster administrative domain. For example, if you want to add a node to administrative domain, you need to add a node to the recovery domain of the CRG with a node role of peer. To start the cluster administrative domain, you start the peer CRG.

By starting and ending the CRG, the process of synchronizing changes can be controlled. When the CRG is ended, changes made to a monitored resource on any node in the domain are not propagated to the rest of the domain. Once the CRG is started, changes which had been made to any monitored resource while it was inactive will be propagated to the rest of the domain. While the CRG is active, changes made to any monitored resource on any active node are propagated dynamically so that the resource remains consistent across the administrative domain. See Monitor a cluster administrative domain for details.

In order to add a node to a cluster administrative domain, you need to add a cluster node to the recovery domain of the peer CRG. When a node is added to the domain, all resources being managed will be created on the new node if they do not exist and will be synchronized with the rest of the administrative domain.

If the cluster administrative domain is deleted, all resources that are defined in the cluster administrative domain are removed from every node in the domain; however the actual resource is not removed from the system. See Monitored resources for details.