Operating Process Engine in an Integration Server Cluster
When two or more Integration Servers are running in a clustered environment, the Process Engines within them are running in a clustered environment as well.
Note: Although the term “Process Engine cluster” may be used from time to time, it actually refers to Process Engines running in an Integration Server cluster.
When you run a process in a clustered Integration Server environment, all Integration Servers that run steps in that process are connected to webMethods Broker (deprecated) using the same client prefix. webMethods Broker (deprecated) serves as the communication link for all of the Process Engines in the Integration Server cluster.
Within the cluster, all steps of a generated and uploaded process model exist on all Integration Server nodes. In other words, from a process point of view, each node in the cluster is an exact copy of the other nodes. The shared webMethods Broker (deprecated) ensures that each process-related message is routed to one and only one Integration Server in the cluster, so there is no duplicate processing.
When two or more Process Engines are running in an Integration Server cluster, all of the Process Engines share a single Process Engine database. Software AG does not provide support for Process Engines to access or share more than one database. See the PDF publication webMethods Integration Server Clustering Guide for information about setting up the external RDBMS.