USB disk passthrough to VM: use USB passthrough or scsi?

[Steve28]

I need some advice on the best way to pass through 3 USB external hard drives to a VM (running openmediavault if that matters).

Right now I have them passed through by passing through the USB device. Would it be "better" to pass them through from the host as scsi devices? Is there an advantage to one over the other?

 

[Dunuin]

As far as I know USB passthrough is purely emulated and therefore slow and unstable. Using "qm set" to passthrough them using virtio SCSI is still virtualized but should be faster and more stable. But its not that great if you plan to remove them from time to time.

 

[Emilien]

You can enable IOMMU and passthrough the entire USB Chipset of the group of ports where are connected your HDDs to your VM.

 

[Steve28]

You can enable IOMMU and passthrough the entire USB Chipset of the group of ports where are connected your HDDs to your VM.

I can't because I use other ports on that same bus for other things in other VMs. But just for my education - would that be faster than either of the other two methods?

 

[chuxxsss]

Hi guys,
new user here I install my USB drives for a truenas setup. All drives are not showing correct drive sizes. I have 2 x 8TB and 2 x 4TB they only show 1.8 TB in total on Promox server.

 

[chuxxsss]

Any help would be apreicated.

 

[Steve28]

Any help would be apreicated.

You need to start a separate thread. This is completely unrelated to this topic