vSAN Skyline health alarm is present for vSAN File Service Node is unhealthy showing a host with "vSAN File Service Node", "VDFS Daemon", and "Root File System" unhealthy with "Workload Balance" as healthy and a description of "File service is not enabled."
DRS in fully automated mode will not allow VMs to run on the host.
The vSAN File Service is in use and working as expected on other nodes in the cluster.
vSAN 7.x and 8.x
After upgrading vCenter server from 7.x to 8.x the OVF repository folders for previous vSAN File Services versions are removed. Without the file repository the service cannot deploy the File Service Virtual Machine (FSVM) on any host.
DRS will migrate any VM away from the host, and avoid placing any there, as the service detects that not all ESX agent VMs are provisioned and powered on.
Reupload the vSAN File Services required OVF files as per this tech doc.
Once the remediation task completes the health check will clear as the FSVM is running with container deployed on the host.