Senior Node
Every cluster contains exactly one senior node that processes the registered list of policy actions on the shared cache and executes events and aggregated metrics. The senior node is responsible for ensuring that all events and metrics written to the shared cache are processed by a node in the cluster. The senior node runs at 15-second intervals in which it scans the shared cache for events and metrics that are scheduled for execution.
When the senior node scans the list of policies and metrics in the shared cache and determines that tasks are in need of processing, it sends a processing event to all the nodes in the cluster. The processing event informs the nodes on the cluster that data must be reported to CentraSite. The first node to respond to the processing event reports the event or metric to CentraSite.
The cluster designates the senior node internally according to which cluster member has been in the cluster the longest. If the senior node becomes disabled, the node left in the cluster that has been part of the cluster the longest takes its place.
Note: The senior node has a different function than the synchronizing node described on
Deployment in a Cluster. The synchronizing node performs a function for deployment and can be a different node for every transaction. The senior node performs functions for event and metric notifications and only changes if the node performing the duties of the senior node is removed from the cluster.