Storage vMotion Error: A general system error occurred: PBM error occurred during PreMigrateCheckCallback: Connection refused

I just tried to perform a Storage vMotion on a VM and received the following error:

I took a look at the services running on the vCSA by running "service-control --status".  It appears the VMware vSphere Profile-Driven Storage Service (vmware-sps) had stopped.

To get the service running, just run the following command:  service-control --start vmware-sps

I was then able to successfully perform a storage vMotion.

Bonus info:
Here's a list of services running on the vsphere 6.X vCSA: