I have recently provisioned two servers that are attached to a Lenovo S3200 with fibre channel. These are the only two servers attached. The servers are running Windows 2016 Nano, and I have installed MPIO and claimed the FC paths. And I created an NTFS volume on the shared SAN disk.
The problem is that when I put a file on the shared volume from one server, it doesn't show up from the other server until after a reboot. I have observed this behavior in both remote PowerShell as well as through the Hyper-V Manager.