When the Data Integration Service runs on a single node, the service and compute components of the Data Integration Service run on the same node. The node must have both the service and compute roles.
A Data Integration Service that runs on a single node can run DTM instances in the Data Integration Service process or in separate DTM processes. Configure the service based on the types of jobs that the service runs.
If you run the Data Integration Service on a single node and you have the high availability option, you can configure back-up nodes in case the primary node becomes unavailable. High availability enables the Service Manager and the Data Integration Service to react to network failures and failures of the Data Integration Service. If a Data Integration Service becomes unavailable, the Service Manager can restart the service on the same node or on a back-up node.