Not sure about the terminology here, but long ago I followed a SpaceInvader video on how to use a "real" Windows installation on a hard disk as a VM in unRAID. It's been running fine for a few years. Now I have added an external SSD to the server as an unassigned device, and want to mount it (or however I can access it) in the VM so I can use it for additional storage. I've read advice on how to do this via the VM configuration page, but the advice typically assumes that there is already a Primary vDisk assigned and then you just click the + sign next to it to add the device as a second vDisk. In my case, there is no Primary vDisk location (entry is "None") and therefore no + sign next to it.

I'm worried that if I simply add the external SSD in that Primary vDisk Location, the VM will try to boot from that device. How can I mount the SSD?

OK, user error here. I just noticed that there is a + sign, it's just that it's right up against the left margin of the page, and it's not visible when my browser window is not at full screen. But I do feel the GUI could be improved so that the + sign is more readily noticeable. I'm using Firefox. in case it's a browser specific issue.

Having said this, the + sign might not be the solution, though. I'm trying to passthrough one of those portable disks in a USB case. It appears as /dev/dis/by-id/usb-JMicron_Tech_000000778899-0:0. But if I enter that as the path for the secondary vDisk, it gets promoted to the Primary vDisk on boot (this shows on the VM config page) and the VM fails to boot (perhaps trying to boot from there) and shuts down. I've tried both USB and VirtIO as the vDisk Bus.

A short while later:

After trying to revert to my original setup, it seems that the original hard disk was Bitlocker encrypted and I needed to enter the recovery key because a USB device had been added to the configuration. So that's a probably reason for the VM appearing to fail. If you don't enter anything at the Bitlocker screen the VM shuts down. I saw this only because I started the VM with the console. I'd experiment further, but it's such a pain entering the Bitlocker key using the function keys, and I'm not sure if there's a simple copy and paste that I can do into the console window. Anyway, if entering the Bitlocker key is required every time I add or remove the USB drive, it's not a practical option for me.

Will try to assign the USB drive as a network share instead.

Edited September 17, 2025Sep 17 by sonofdbn
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