What does the controlling node do?

start of changeThe controlling node is the primary point of contact between IBM® Systems Director and the PowerHA® SystemMirror cluster. All actions are performed exclusively on this node and all information is retrieved exclusively from this node. end of change

start of changeIBM Systems Director uses the controlling node to communicate with the PowerHA SystemMirror cluster for cluster-related actions. The controlling node is the interface between IBM Systems Director and the cluster, and it is the node upon which all IBM Systems Director actions are performed. If, for any reason, PowerHA SystemMirror is unable to contact the controlling node, PowerHA SystemMirror reassigns the controlling node to a node that it can contact successfully. end of change

start of changeWhen you synchronize the cluster, all changes made on the controlling node are propagated to all the other cluster nodesend of change