@Override
    public void markedAsSeniorClusterMember() {
        LOGGER.info("This node ({}/{}) is now the senior member", xmppServer.getNodeID(), xmppServer.getServerInfo().getHostname());
    }
Monitors the state of the cluster, and warns admins when nodes leave or rejoin the cluster
xmppserver/src/main/java/org/jivesoftware/openfire/cluster/ClusterMonitor.java