When a service that is not a Qlik Sense Repository Service (QRS) starts, it contacts its local QRS to get configuration parameters. If the service is not (yet) configured to start, it periodically checks back with the local QRS. For information on the Qlik Sense services, see Services.
Depending on the type of Qlik Sense deployment, the Qlik Sense Scheduler Service (QSS) runs as master, slave, or both on a node.