We are using jGroups to build two clusters: "server" and "app". They are independent clusters, running on different machines (communicating with each-other over JMS). Some of our code needs to run on only one node in a cluster, so we use the "coordinator" / master concept in jGroups to choose the node where to run that code.
We have yet another requirement: we need to notify server admin, when any of our cluster nodes die. We could have each cluster node monitor for membership changes, but we cannot send failure notifications from "app" cluster nodes, only from "server" cluster nodes.
Finally, the question: is it possible to join a jGroups channel/cluster without participating in the coordinator/master election? So that "server" cluster nodes could join "app" cluster as observer-only members (receiving "view changed" events, but not participating in the elections)?