By default, when you install and deploy a multi-instance system, the system automatically runs each service (except Dashboard) on its required number of instances. For example, the Index service runs on three instances.
However, if you've installed more than four instances, some instances might not be running any services at all. As a result, these instances are underused. You should manually distribute services to run across all instances in your system.
Important: Before trying to scale the Clustered-File-System service, see Clustered-File-System service considerations.