Op-mon to use one IP and daemon within a cluster
1) make sure, slave nodes -> master node can connect over port 2080
2) on master node, add to /etc/xroad/conf.d/local.ini
[op-monitor]
host = <master-internal-IP>
3) on master node
service xroad-proxy restart
4) on slave nodes
service xroad-proxy restart
service xroad-opmon stop
service xroad-opmon mask