Cluster Support Limitations Some cluster vendors, such as Veritas allow the use of parallel groups. A parallel group can run concurrently on multiple systems in the cluster at a time. A parallel service group is more complex than a failover group. It requires an application that can safely be started on more than one system at a time with no threat of data corruption, or that the data being accessed is local to each server. TIBCO Administrator does not support parallel groups. The main architecture limitation is that only one copy of a TIBCO Hawk Agent instance can be running from one system in the cluster at a time. Cluster vendors also provide load balanced cluster groups. A load balanced cluster solution helps to implement an enterprise-wide scalable solution for incoming TCP/IP traffic. This solution is commonly used for web server applications. Applications that are deployed to a load balanced cluster run separate copies of the applications on each host machine. Network load balancing distributes incoming client requests across the machines in the cluster. TIBCO applications are intended to work in failover cluster environments, not in load balanced clusters. Load-balanced cluster solutions are not addressed in this document.