The 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.
IBM 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.
When you synchronize the cluster, all changes made on
the controlling node are propagated to all the other cluster nodes