Rear USB unstable / not working

[donativo]

Hello,

I am going to use the HM80 as mini server with Unraid or Proxmox Linux. After a long time I learned that the HM80 has some huge issues with the rear USB ports.

Issues:
- Setup of Proxmox not able to finish
- Running Unraid from USB stick attached to any rear USB port fails

After I disabled IOMMU in Bios the rear ports were able to execute the software as it should. But i think the stability is still bad. Attaching a Fantec USB tower with 8 drives worked well for a while, like 2-3h, but then it crashed and the whole HDD tower is not coming back. The log is full with USB errors in Unraid. But now even not on the front usb ports. :-/

Attaching the Fantec Tower to another PC comes up without any issues.

Please check what is going on - it seams I am not alone with this or very similar issues on the HM80



American Megatrends Inc., Version 5.16
BIOS dated: Wed 11 Aug 2021 12:00:00 AM PDT

 

[HandfeGER]

Unfortunately I have the same problem with HM80:
- Setup unraid or other Linux OS via the rear USB ports is impossible
- via front USB ports it works

American Megatrends Inc., Version 5.16
BIOS dated: Wed 11 Aug 2021 12:00:00 AM PDT

 

[joey]

Unfortunately I have the same problem with HM80:
- Setup unraid or other Linux OS via the rear USB ports is impossible
- via front USB ports it works

American Megatrends Inc., Version 5.16
BIOS dated: Wed 11 Aug 2021 12:00:00 AM PDT

Please disable IOMMU option in bios.

 

[HandfeGER]

but i need IOMMU to passthrough 2 ethernet Controller/NICs

 

[joey]

There is currently no perfect solution. Maybe you can solve it by expanding the USB port, I hope this information is helpful to you, thank you

 

[27leguas]

Disabling IOMMU is one possible solution but disables some important functions for virtualization performance.
If you don't use Virtual Machines its OK but there is another solution that don't penalize performance or functions.

IOMMU in one very important source of boot and USB problems in Linux.
I have created a detailed documentation on this topics:

• What IOMMU controller does?
• Different fixes for boot and USB problems related to IOMMU in Linux
• How to tell if you are running on an emulated IOMMU or a Hardware one?
• How to check if hardware IOMMU controller and passthrough are enabled?

I have posted the documentation in the Ryzen 5 4500U section:
https://bbs.minisforum.com/threads/the-iommu-issue-boot-and-usb-problems.2180/