USB Passthrough preventing boot if device not connected.

[BrendonB]

I have a Debian box running Octoprint and have USB to my 3d Printer passed through. Obviously there have been times where there has been a reboot of the host or CT and the printer is not on or connected.
This prevents the box from booting with the error: TASK ERROR: Device /dev/ttyUSB0 does not exist
Is there any way/option to allow this to boot regardless?

 

[sw-omit]

Not tested, but just a thought for a (hardware) fix:
Have you tried connecting an USB-hub to the server/PC port and having the 3D-printer hooked up to that?

The hub itself is the "device" that you hook up, and since it will get its power from the PC it is always on/there.
It might then forward all the ports on the hub, filled or not, to the VM.
Gives the added benefit of being able to also plug in USB's from other devices, or plug in more 3D-printers in the future.

Again, not tested, but if you have something like that lying around or can borrow it / get it for cheap, worth the shot, not?

 

[BrendonB]

Thanks sw-omit but this doesnt work unfortunately as you map directly to the port or the device ID for the passthrough. Any other ideas would be appreciated

 

[sw-omit]

Shame, would have thought selecting the device-ID of the hub (or the port the hub is connected to your PC), since it is an "active" component so to speak, would be possible / would work.

Don't really have any direct other recommendations, since I also don't use this setup, other then maybe using usb-over-ethernet, so that you don't even need to passthrough anything (and are more flexible probably with the position of your devices)

 

[leesteken]

Shame, would have thought selecting the device-ID of the hub (or the port the hub is connected to your PC), since it is an "active" component so to speak, would be possible / would work.

That would be great (especially when the limit was 5 USB devices) and sometimes even the Proxmox staff assumes it works, but unfortunately it did not and does not.

This prevents the box from booting with the error: TASK ERROR: Device /dev/ttyUSB0 does not exist
Is there any way/option to allow this to boot regardless?

Hot-plug does not work with containers, unfortunately. Either the device is there from the start or you get errors. With VMs, you can add USB devices on the fly and with some udev-rules or USB-port passthrough it does work. You might be able to concoct a hookscript that removes the passthrough from the configuration and automatically reboots the container when a udev rule detects a plugin of the device. Or just use a VM with a specific USB port.