Re: [PVE-User] USB device passthrough

Re: [PVE-User] USB device passthrough

[Florian Heiber]

[-- Attachment #1: Type: text/plain, Size: 277 bytes --]

Thank you, Arjen! This lead me to the solution: I was missing the mode parameter in my udev configuration. Now I can read my meters from the container!

Thanks again!
– Florian

> Am 29.12.2021 um 12:14 schrieb Arjen via pve-user <pve-user@lists.proxmox.com>:
> 
> 

[-- Attachment #2: Type: text/plain, Size: 165 bytes --]

> _______________________________________________
> pve-user mailing list
> pve-user@lists.proxmox.com
> https://lists.proxmox.com/cgi-bin/mailman/listinfo/pve-user

[PVE-User] USB device passthrough

[Florian Heiber]

Hi all,

I’m trying to pass multiple USB devices from my host through into my container. I’ve followed a few tutorials ([1], [2]) that describe the process, but I can’t get it to work.

What have I done?

I have connected the USB devices to my host. I can confirm that they work via /dev/ttyUSB0, etc. I created a udev rule to consistently have them available as /dev/reader0, etc. I can also confirm that I can use those aliases as if I was using the original device. I consider this a success.

I updated the container’s configuration at, in this case, /etc/pve/lxc/109.conf to include my mount points:

lxc.cgroup.devices.allow: c 7:* rwm
lxc.mount.entry: /dev/reader0 dev/reader0 none bind,optional,create=file

After a reboot of the container, the device appears as configured. Unfortunately, I looks like I have some issues with my permissions. When I try to print out the data coming from the reader, I only see a 

florian@datalogger:~$ cat /dev/reader0 | od -tx1
cat: /dev/reader0: Permission denied
0000000

This does, however, work as expected when I run this on the host itself.

Does anyone see what I’m missing here? One point I’m not too sure about is the major part in the lxc.cgroup.devices.allow line. I suppose it should reflect the major part of the device I'm trying to expose, but some tutorials used the one of the original device (/dev/ttyUSB0 in my case, 188) here.

Thank you for your time!

All the best,
– Florian

[1]: https://drozmotix.github.io/languages/en/BasicSetup/03.ProxmoxLXC.html#what-is-lxc
[2]: https://deviant.engineer/2016/11/lxc-passthrough/