Planning for a clustered environment
Configuration in a clustered environment takes planning to ensure the optimal performance of your system. Whether you configure your system to include clusters depends on your business needs.
Plan for a cluster configuration that accommodates your environment. In addition to assuring the correct type of hardware and the applicable software, you must set up a failover pattern.
When a node fails or needs to be taken offline, which node or nodes in the cluster picks up the transaction processing? In a two-node cluster, there is little planning necessary. In a more complex arrangement, you want to consider how your transaction processing is best handled. A form of load balancing among your nodes needs to be accounted for so that you maintain peak performance. Another consideration is to ensure that your customers do not see any lag and little drop in productivity.
Microsoft Cluster Servers and Microsoft Failover Clusters require each IBM Storage Protect server instance to have a private set of disk resources. Although nodes can share disk resources, only one node can actively control a disk at a time.
Is one configuration better than the other? To determine your best installation, you need to look at the differences in performance and cost. Assume that you have an IBM Storage Protect server-dedicated cluster whose nodes have comparable power. During failover, the performance of a configuration might degrade because one node must manage both IBM Storage Protect cluster instances. If each node handles 100 clients in a normal operation, one node must handle 200 clients during a failure.