The PowerCenter Integration Service runs PowerCenter sessions and workflows. When you configure the PowerCenter Integration Service, you can specify where you want it to run:
On a grid. When you configure the service to run on a grid, it can run on multiple nodes at a time. The PowerCenter Integration Service dispatches tasks to available nodes assigned to the grid. If you do not have the high availability option, the task fails if any service process or node becomes unavailable. If you have the high availability option, failover and recovery is available if a service process or node becomes unavailable.
On nodes. If you have the high availability option, you can configure the service to run on multiple nodes. By default, it runs on the primary node. If the primary node is not available, it runs on a backup node. If the service process fails or the node becomes unavailable, the service fails over to another node. If you do not have the high availability option, you can configure the service to run on one node.