I've set up a Win Srv2012 with Hyper-V with a 7TB iSCSI NAS attached to the Hyper-V host. It's visible as an E: drive on the Hyper-V host.
I've then created a 3TB VHD on the E: drive and assigned it to the host as a SCSI drive.
Whenever the Virtual machine access this new VHD a lot - could be copying 1 TB of data to the new VHD or even just formatting the new VHD from within the Virtual Machine, it suddenly disappears from within the Virtual Machine. Not even a rescan can detect the SCSI VHD again.
The disk is still listed as attached in the VM Settings until you reboot the VM - then its gone and all that is left is the SCSI controller.
There are no errors on the event log(s).
The Hyper-V host is running on a Dell Desktop machine with a Core i7 CPU, 32Gb RAM and a local 480Gb Intel SSD. There are no issues with the local disk.
Any help or directions would be much appreciated. I'm out of ideas myself (except bying a "real" $10K server for this, but it may be a bit of an overkill for this project.