[SOLVED] Using USB 3.0 HDD enclosure with an OMV Proxmox VM

[erreib]

Hello, hoping this is an ok place to post my question. I have an Intel NUC running Proxmox 8.1.5. I have a Teramaster 4 bay USB 3.0 enclosure connected with 4 hard drives attached. I would like to pass through the drives to an OMV VM via the USB passthrough function, then use mergerfs to layer and serve the drives on a single SMB network drive.

This all works great in theory, however when transferring files between the drives within the enclosure, the read/write activity seems to cause the USB driver and VM to fail. I get a "xhci hcd error transfer event rb dma ptr not part of current td ep_index 2 comp_code 4" message. Does anyone know what might be the best way for me to troubleshoot this? I have tried to eliminate several potential causes but have not had any success yet. The VM only seems to fail when multiple drives within the enclosure are actively reading or writing, things work fine when only dealing with one drive. There seem to be other users dealing with a related error in another thread: https://forum.proxmox.com/threads/xhci_hcd-error.130321/ . Thanks in advance for any potential tips!

 

[Dunuin]

I would like to pass through the drives to an OMV VM via the USB passthrough function, then use mergerfs to layer and serve the drives on a single SMB network drive.

USB passthrough is emulated and not paravirtualized like disk passthrough. So not great for applications where low latency or thorughput is required. I would make use of disk passthrough instead to skip the whole USB emulation: https://pve.proxmox.com/wiki/Passthrough_Physical_Disk_to_Virtual_Machine_(VM)

And keep in mind that USB in general isn't that reliable and all I heard about any multi-disk-usb-enclosure are problems...

 

[erreib]

USB passthrough is emulated and not paravirtualized like disk passthrough. So not great for applications where low latency or thorughput is required. I would make use of disk passthrough instead to skip the whole USB emulation: https://pve.proxmox.com/wiki/Passthrough_Physical_Disk_to_Virtual_Machine_(VM)

And keep in mind that USB in general isn't that reliable and all I heard about any multi-disk-usb-enclosure are problems...

Think this is just the link I need! Gonna give it a try. Yes totally agree on the USB HDD enclosures being on the wonky side. Planning on moving up to a fuller scale DAS with better IO at some point but obviously the NUC has limitations. Thanks!

 

[erreib]

USB passthrough is emulated and not paravirtualized like disk passthrough. So not great for applications where low latency or thorughput is required. I would make use of disk passthrough instead to skip the whole USB emulation: https://pve.proxmox.com/wiki/Passthrough_Physical_Disk_to_Virtual_Machine_(VM)

And keep in mind that USB in general isn't that reliable and all I heard about any multi-disk-usb-enclosure are problems...

Thanks again, can confirm the disk passthrough appears to be working perfectly while reading/writing from multiple disks in the array. Works great!