Install the Domain Orchestrator › Prerequisites to Installing the Domain Orchestrator › Planning the Locations of Supporting Components

Planning the Locations of Supporting Components

Part of planning a CA Process Automation system is determining what new components you can colocate on the same host with the CA Process Automation Domain Orchestrator and which ones to install on separate hosts. Let us consider these components of a CA Process Automation network.

• JDK - must be colocated
• CA Embedded Entitlements Manager (CA EEM) - can be colocated, but not recommended
• Databases for the CA Process Automation data stores - can be colocated, but not recommended
• Load balancer (if planning to cluster) - cannot be colocated
• Other Orchestrators - cannot be colocated
• Cluster Nodes - cannot be colocated
• NTP server - external to network
• CA SiteMinder (optional) - can be colocated, but not recommended

Each cluster node and each Orchestrator is typically installed on a separate host. The NTP server can be external to the network.

For a lightly loaded CA Process Automation, you could install the following entities on the same host on which you installed the Domain Orchestrator:

• CA EEM.
• Database for the Library, Reports, and Runtime data stores.

Consider the following factors when determining whether to colocate entities or use multiple hosts:

• Characteristics of the host

  Major factors include the quantity and speed of CPUs, memory, disk storage and networks.

• Volume of processes.

  Consider not only the total number of processes, but also their max sustained rates during periods of peak activity.

• Process implementation.

  Not all processes are equal. Some processes have few operators, others have hundreds. Some processes contain many CPU intensive activities, while others spend most of their time waiting for events or user interactions. This variability makes it difficult to specify loading in terms of process volume/rate. Even at the finer granularity of operators, throughput varies.

• Required level of responsiveness.

  Real-time responsiveness is never attainable with the current implementation. However, even less stringent requirements factor into when more hardware for additional Orchestrators come into play. With a stringent SLA, the system needs more spare capacity so that the peak periods still perform well. Without an SLA, the system needs only sufficient capacity to cover the average load.

• Intensity of usage for shared components.

  Consider what else the CA EEM and the RDBMS are used for.

In anticipation of future growth, we recommend against colocating CA EEM and the database with the Domain Orchestrator. The only sure way to determine when you have enough resources is by actual full load testing.