CTX with no particular conf and USB

rjcab

Active Member
Mar 1, 2021
117
1
38
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Hello,

Here below my conf of my ctx:

Code:
root@pve:~# cat /etc/pve/lxc/109.conf
#lxc.cgroup.devices.allow%3A c 189%3A43 rwm
#lxc.mount.entry%3A /dev/bus/usb/001/043 dev/ttyUSB1 none bind,optional,create=file
arch: amd64
cores: 1
features: nesting=1
hostname: nad
memory: 512
net0: name=eth0,bridge=vmbr0,gw=192.168.1.1,hwaddr=BC:24:11:DE:6C:41,ip=192.168.1.183/24,type=veth
ostype: debian
rootfs: local-lvm:vm-109-disk-0,size=8G
swap: 512
unprivileged: 1
root@pve:~#

When I am on my CTX:

Code:
root@nad:~#
root@nad:~# lsusb
Bus 002 Device 004: ID 0b95:1790 ASIX Electronics Corp. AX88179 Gigabit Ethernet
Bus 002 Device 003: ID 2109:0817 VIA Labs, Inc. USB3.0 Hub             
Bus 002 Device 002: ID 07ab:fc9f Freecom Technologies Mobile Drive XXS
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 024: ID 0951:1666 Kingston Technology DataTraveler 100 G3/G4/SE9 G2/50 Kyson
Bus 001 Device 021: ID 0bc2:2312 Seagate RSS LLC Expansion
Bus 001 Device 007: ID 8087:0029 Intel Corp. AX200 Bluetooth
Bus 001 Device 046: ID 2575:0401 Weida Hi-Tech Co., Ltd. CoolTouchR System           
Bus 001 Device 020: ID 1cf1:0030 Dresden Elektronik ZigBee gateway [ConBee II]
Bus 001 Device 012: ID 0463:ffff MGE UPS Systems UPS
Bus 001 Device 013: ID 1a40:0101 Terminus Technology Inc. Hub
Bus 001 Device 008: ID 214b:7250 Huasheng Electronics USB2.0 HUB
Bus 001 Device 005: ID 174c:2074 ASMedia Technology Inc. ASM1074 High-Speed hub
Bus 001 Device 004: ID 12d1:140c Huawei Technologies Co., Ltd. E180v
Bus 001 Device 014: ID 2109:8817 VIA Labs, Inc. USB Billboard Device   
Bus 001 Device 028: ID 0658:0200 Sigma Designs, Inc. Aeotec Z-Stick Gen5 (ZW090) - UZB
Bus 001 Device 009: ID 1a40:0101 Terminus Technology Inc. Hub
Bus 001 Device 006: ID 067b:2303 Prolific Technology, Inc. PL2303 Serial Port / Mobile Phone Data Cable
Bus 001 Device 048: ID 067b:2303 Prolific Technology, Inc. PL2303 Serial Port / Mobile Phone Data Cable
Bus 001 Device 003: ID 2109:2817 VIA Labs, Inc. USB2.0 Hub             
Bus 001 Device 002: ID 0403:6001 Future Technology Devices International, Ltd FT232 Serial (UART) IC
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
root@nad:~#

Why I got all USB devices whereas I do not specify this kind of conf:

Code:
lxc.cgroup.devices.allow: c 189:43 rwm lxc.mount.entry:
/dev/bus/usb/001/043 dev/ttyUSB1 none bind,optional,create=file

Also I just want to get this device on my CTX:
Code:
Bus 001 Device 048: ID 067b:2303 Prolific Technology, Inc. PL2303 Serial Port / Mobile Phone Data Cable

But I have two same devices. So I should do and report bus & device number but device number increases may be after reboot ?

Code:
root@pve:~# ls -l /dev/bus/usb/001/048
crw-rw-r-- 1 root root 189, 47 Oct  8 06:56 /dev/bus/usb/001/048
root@pve:~#
 
Why I got all USB devices
lsusb listing all USB devices is expected, since it reads the USB device list out of the sysfs which is mounted into the container. But you cannot access the USB device without explicitly passing it through.

lxc.cgroup.devices.allow: c 189:43 rwm lxc.mount.entry: /dev/bus/usb/001/043 dev/ttyUSB1 none bind,optional,create=file
There is a simpler way to pass a device through: Resources -> Add -> Device Passthrough

But I have two same devices. So I should do and report bus & device number but device number increases may be after reboot ?
If the device path changes across reboots, you can setup a udev rule that creates a symlink pointing to the device node from a persistent path. Then pass the symlink to the container via device passthrough.
 
Thanks for the prompt reply:

so

1759915623136.png

I understand that the path must be /dev/xxx but I don't know it as it is not configured yet in the CTX till the start of the CTX ? e

1759915662285.png
 
Thanks for the prompt reply:

so

1759915623136.png
This is used for VMs, not containers.

I understand that the path must be /dev/xxx but I don't know it as it is not configured yet in the CTX till the start of the CTX ? e

1759915662285.png
Running lsusb on the host outputs the bus & device number of each USB device:
Code:
Bus 001 Device 001: ID ...
Bus 001 Device 002: ID ...
Bus 002 Device 001: ID ...
...
This corresponds to /dev/bus/usb/<bus>/<device>.
 
sorry, I am lost. My objective is to have my USB device attached to my container.
So for this, we can not use the UI because only for VM. We need to custom the /etc/pve/lxc/109.conf right ?
 
So for this, we can not use the UI because only for VM. We need to custom the /etc/pve/lxc/109.conf right ?
No, you can configure container device passthrough in the Web UI. Select the container -> Resources -> Add -> Device Passthrough.

When I wrote "This is used for VMs, not containers.", I was referring to your first screenshot which shows Datacenter -> Resource Mappings -> USB Devices.
 
Ok, I got it:

on my CTX:

1759918547554.png

My script try to open the device but I got an error: . It works with a VM hosted on Proxmox.

Code:
root@nad:/dev/bus/usb/001# python3 /root/nad-rs232-rest/nad-rs232-rest.py
2025-10-08 10:14:15,727 - INFO - Starting mqtt thread
2025-10-08 10:14:15,730 - DEBUG - [MQTT] Connected to broker (result code 0)
2025-10-08 10:14:15,731 - INFO - Starting serial port thread
2025-10-08 10:14:15,731 - CRITICAL - [SERIAL] Could not open /dev/bus/usb/001/048
 * Serving Flask app 'nad-rs232-rest'

So I stop the container and check but 048 doesn't exsite anymore. Proxmox did not restart.

Code:
root@pve:~# lsusb
...
Bus 001 Device 009: ID 1a40:0101 Terminus Technology Inc. Hub
Bus 001 Device 006: ID 067b:2303 Prolific Technology, Inc. PL2303 Serial Port / Mobile Phone Data Cable
Bus 001 Device 049: ID 067b:2303 Prolific Technology, Inc. PL2303 Serial Port / Mobile Phone Data Cable
Bus 001 Device 003: ID 2109:2817 VIA Labs, Inc. USB2.0 Hub
Bus 001 Device 002: ID 0403:6001 Future Technology Devices International, Ltd FT232 Serial (UART) IC
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
root@pve:~# ls -l /dev/bus/usb/00
001/ 002/
root@pve:~# ls -l /dev/bus/usb/001/0
001  002  003  004  005  006  007  008  009  012  013  014  020  021  024  028  046  049
root@pve:~# ls -l /dev/bus/usb/001/049
crw-rw-r-- 1 root root 189, 48 Oct  8 12:12 /dev/bus/usb/001/049
root@pve:~#

Also I can't play with ID as I have 2 same devices, one is dedicated for one VM to control an air flow the other one for my CTX 109.

How can I proceed with this kind of conf ?

thanks
 
So I stop the container and check but 048 doesn't exsite anymore. Proxmox did not restart.
As I wrote, for such cases setting up a udev rule makes sense.

Also I can't play with ID as I have 2 same devices, one is dedicated for one VM to control an air flow the other one for my CTX 109.
udev rules can still differentiate two same devices by their serial numbers.

2025-10-08 10:14:15,731 - CRITICAL - [SERIAL] Could not open /dev/bus/usb/001/048
Also since it seems that you are trying to read from a serial device, using /dev/bus/usb/... might not work. Instead you will want to look for something like /dev/ttyACM0 or /dev/ttyUSB0.
 
Last edited:
Thanks for your time. In my case only the serial will make the difference:

Code:
root@pve:/mnt# udevadm info --name=/dev/bus/usb/001/049 --attribute-walk

Udevadm info starts with the device specified by the devpath and then
walks up the chain of parent devices. It prints for every device
found, all possible attributes in the udev rules key format.
A rule to match, can be composed by the attributes of the device
and the attributes from one single parent device.

  looking at device '/devices/pci0000:00/0000:00:14.0/usb1/1-3/1-3.1':
    KERNEL=="1-3.1"
    SUBSYSTEM=="usb"
    DRIVER=="usb"
    ATTR{authorized}=="1"
    ATTR{avoid_reset_quirk}=="0"
    ATTR{bConfigurationValue}=="1"
    ATTR{bDeviceClass}=="00"
    ATTR{bDeviceProtocol}=="00"
    ATTR{bDeviceSubClass}=="00"
    ATTR{bMaxPacketSize0}=="64"
    ATTR{bMaxPower}=="100mA"
    ATTR{bNumConfigurations}=="1"
    ATTR{bNumInterfaces}==" 1"
    ATTR{bcdDevice}=="0400"
    ATTR{bmAttributes}=="a0"
    ATTR{busnum}=="1"
    ATTR{configuration}==""
    ATTR{devnum}=="49"
    ATTR{devpath}=="3.1"
    ATTR{idProduct}=="2303"
    ATTR{idVendor}=="067b"
    ATTR{ltm_capable}=="no"
    ATTR{manufacturer}=="Prolific Technology Inc. "
    ATTR{maxchild}=="0"
    ATTR{power/active_duration}=="14094285"
    ATTR{power/async}=="enabled"
    ATTR{power/autosuspend}=="2"
    ATTR{power/autosuspend_delay_ms}=="2000"
    ATTR{power/connected_duration}=="14094285"
    ATTR{power/control}=="on"
    ATTR{power/level}=="on"
    ATTR{power/persist}=="1"
    ATTR{power/runtime_active_kids}=="0"
    ATTR{power/runtime_active_time}=="14094019"
    ATTR{power/runtime_enabled}=="forbidden"
    ATTR{power/runtime_status}=="active"
    ATTR{power/runtime_suspended_time}=="0"
    ATTR{power/runtime_usage}=="1"
    ATTR{power/wakeup}=="disabled"
    ATTR{power/wakeup_abort_count}==""
    ATTR{power/wakeup_active}==""
    ATTR{power/wakeup_active_count}==""
    ATTR{power/wakeup_count}==""
    ATTR{power/wakeup_expire_count}==""
    ATTR{power/wakeup_last_time_ms}==""
    ATTR{power/wakeup_max_time_ms}==""
    ATTR{power/wakeup_total_time_ms}==""
    ATTR{product}=="USB-Serial Controller D"
    ATTR{quirks}=="0x0"
    ATTR{removable}=="unknown"
    ATTR{remove}=="(not readable)"
    ATTR{rx_lanes}=="1"
    ATTR{speed}=="12"
    ATTR{tx_lanes}=="1"
    ATTR{urbnum}=="19"
    ATTR{version}==" 1.10"

  looking at parent device '/devices/pci0000:00/0000:00:14.0/usb1/1-3':
    KERNELS=="1-3"
    SUBSYSTEMS=="usb"
    DRIVERS=="usb"
    ATTRS{authorized}=="1"
    ATTRS{avoid_reset_quirk}=="0"
    ATTRS{bConfigurationValue}=="1"
    ATTRS{bDeviceClass}=="09"
    ATTRS{bDeviceProtocol}=="02"
    ATTRS{bDeviceSubClass}=="00"
    ATTRS{bMaxPacketSize0}=="64"
    ATTRS{bMaxPower}=="0mA"
    ATTRS{bNumConfigurations}=="1"
    ATTRS{bNumInterfaces}==" 1"
    ATTRS{bcdDevice}=="0433"
    ATTRS{bmAttributes}=="e0"
    ATTRS{busnum}=="1"
    ATTRS{configuration}==""
    ATTRS{devnum}=="3"
    ATTRS{devpath}=="3"
    ATTRS{idProduct}=="2817"
    ATTRS{idVendor}=="2109"
    ATTRS{ltm_capable}=="no"
    ATTRS{manufacturer}=="VIA Labs, Inc.         "
    ATTRS{maxchild}=="5"
    ATTRS{physical_location/dock}=="no"
    ATTRS{physical_location/horizontal_position}=="left"
    ATTRS{physical_location/lid}=="no"
    ATTRS{physical_location/panel}=="top"
    ATTRS{physical_location/vertical_position}=="upper"
    ATTRS{power/active_duration}=="196027693"
    ATTRS{power/async}=="enabled"
    ATTRS{power/autosuspend}=="0"
    ATTRS{power/autosuspend_delay_ms}=="0"
    ATTRS{power/connected_duration}=="196027693"
    ATTRS{power/control}=="auto"
    ATTRS{power/level}=="auto"
    ATTRS{power/runtime_active_kids}=="4"
    ATTRS{power/runtime_active_time}=="196027451"
    ATTRS{power/runtime_enabled}=="enabled"
    ATTRS{power/runtime_status}=="active"
    ATTRS{power/runtime_suspended_time}=="0"
    ATTRS{power/runtime_usage}=="0"
    ATTRS{power/wakeup}=="disabled"
    ATTRS{power/wakeup_abort_count}==""
    ATTRS{power/wakeup_active}==""
    ATTRS{power/wakeup_active_count}==""
    ATTRS{power/wakeup_count}==""
    ATTRS{power/wakeup_expire_count}==""
    ATTRS{power/wakeup_last_time_ms}==""
    ATTRS{power/wakeup_max_time_ms}==""
    ATTRS{power/wakeup_total_time_ms}==""
    ATTRS{product}=="USB2.0 Hub             "
    ATTRS{quirks}=="0x0"
    ATTRS{removable}=="removable"
    ATTRS{remove}=="(not readable)"
    ATTRS{rx_lanes}=="1"
    ATTRS{serial}=="000000000"
    ATTRS{speed}=="480"
    ATTRS{tx_lanes}=="1"
    ATTRS{urbnum}=="247"
    ATTRS{version}==" 2.10"

  looking at parent device '/devices/pci0000:00/0000:00:14.0/usb1':
    KERNELS=="usb1"
    SUBSYSTEMS=="usb"
    DRIVERS=="usb"
    ATTRS{authorized}=="1"
    ATTRS{authorized_default}=="1"
    ATTRS{avoid_reset_quirk}=="0"
    ATTRS{bConfigurationValue}=="1"
    ATTRS{bDeviceClass}=="09"
    ATTRS{bDeviceProtocol}=="01"
    ATTRS{bDeviceSubClass}=="00"
    ATTRS{bMaxPacketSize0}=="64"
    ATTRS{bMaxPower}=="0mA"
    ATTRS{bNumConfigurations}=="1"
    ATTRS{bNumInterfaces}==" 1"
    ATTRS{bcdDevice}=="0608"
    ATTRS{bmAttributes}=="e0"
    ATTRS{busnum}=="1"
    ATTRS{configuration}==""
    ATTRS{devnum}=="1"
    ATTRS{devpath}=="0"
    ATTRS{idProduct}=="0002"
    ATTRS{idVendor}=="1d6b"
    ATTRS{interface_authorized_default}=="1"
    ATTRS{ltm_capable}=="no"
    ATTRS{manufacturer}=="Linux 6.8.12-15-pve xhci-hcd"
    ATTRS{maxchild}=="16"
    ATTRS{power/active_duration}=="196028205"
    ATTRS{power/async}=="enabled"
    ATTRS{power/autosuspend}=="0"
    ATTRS{power/autosuspend_delay_ms}=="0"
    ATTRS{power/connected_duration}=="196028204"
    ATTRS{power/control}=="auto"
    ATTRS{power/level}=="auto"
    ATTRS{power/runtime_active_kids}=="6"
    ATTRS{power/runtime_active_time}=="196028201"
    ATTRS{power/runtime_enabled}=="enabled"
    ATTRS{power/runtime_status}=="active"
    ATTRS{power/runtime_suspended_time}=="0"
    ATTRS{power/runtime_usage}=="0"
    ATTRS{power/wakeup}=="disabled"
    ATTRS{power/wakeup_abort_count}==""
    ATTRS{power/wakeup_active}==""
    ATTRS{power/wakeup_active_count}==""
    ATTRS{power/wakeup_count}==""
    ATTRS{power/wakeup_expire_count}==""
    ATTRS{power/wakeup_last_time_ms}==""
    ATTRS{power/wakeup_max_time_ms}==""
    ATTRS{power/wakeup_total_time_ms}==""
    ATTRS{product}=="xHCI Host Controller"
    ATTRS{quirks}=="0x0"
    ATTRS{removable}=="unknown"
    ATTRS{remove}=="(not readable)"
    ATTRS{rx_lanes}=="1"
    ATTRS{serial}=="0000:00:14.0"
    ATTRS{speed}=="480"
    ATTRS{tx_lanes}=="1"
    ATTRS{urbnum}=="213"
    ATTRS{version}==" 2.00"

  looking at parent device '/devices/pci0000:00/0000:00:14.0':
    KERNELS=="0000:00:14.0"
    SUBSYSTEMS=="pci"
    DRIVERS=="xhci_hcd"
    ATTRS{ari_enabled}=="0"
    ATTRS{broken_parity_status}=="0"
    ATTRS{class}=="0x0c0330"
    ATTRS{consistent_dma_mask_bits}=="64"
    ATTRS{d3cold_allowed}=="1"
    ATTRS{dbc}=="disabled"
    ATTRS{dbc_bInterfaceProtocol}=="01"
    ATTRS{dbc_bcdDevice}=="0010"
    ATTRS{dbc_idProduct}=="0010"
    ATTRS{dbc_idVendor}=="1d6b"
    ATTRS{device}=="0x43ed"
    ATTRS{dma_mask_bits}=="64"
    ATTRS{driver_override}=="(null)"
    ATTRS{enable}=="1"
    ATTRS{index}=="2"
    ATTRS{irq}=="136"
    ATTRS{label}=="Onboard - Other"
    ATTRS{local_cpulist}=="0-15"
    ATTRS{local_cpus}=="ffff"
    ATTRS{msi_bus}=="1"
    ATTRS{msi_irqs/136}=="msi"
    ATTRS{msi_irqs/137}=="msi"
    ATTRS{msi_irqs/138}=="msi"
    ATTRS{msi_irqs/139}=="msi"
    ATTRS{msi_irqs/140}=="msi"
    ATTRS{msi_irqs/141}=="msi"
    ATTRS{msi_irqs/142}=="msi"
    ATTRS{msi_irqs/143}=="msi"
    ATTRS{numa_node}=="-1"
    ATTRS{power/async}=="enabled"
    ATTRS{power/control}=="auto"
    ATTRS{power/runtime_active_kids}=="2"
    ATTRS{power/runtime_active_time}=="196029297"
    ATTRS{power/runtime_enabled}=="enabled"
    ATTRS{power/runtime_status}=="active"
    ATTRS{power/runtime_suspended_time}=="0"
    ATTRS{power/runtime_usage}=="0"
    ATTRS{power/wakeup}=="enabled"
    ATTRS{power/wakeup_abort_count}=="0"
    ATTRS{power/wakeup_active}=="0"
    ATTRS{power/wakeup_active_count}=="0"
    ATTRS{power/wakeup_count}=="0"
    ATTRS{power/wakeup_expire_count}=="0"
    ATTRS{power/wakeup_last_time_ms}=="0"
    ATTRS{power/wakeup_max_time_ms}=="0"
    ATTRS{power/wakeup_total_time_ms}=="0"
    ATTRS{power_state}=="D0"
    ATTRS{remove}=="(not readable)"
    ATTRS{rescan}=="(not readable)"
    ATTRS{revision}=="0x11"
    ATTRS{subsystem_device}=="0x7270"
    ATTRS{subsystem_vendor}=="0x8086"
    ATTRS{vendor}=="0x8086"

  looking at parent device '/devices/pci0000:00':
    KERNELS=="pci0000:00"
    SUBSYSTEMS==""
    DRIVERS==""
    ATTRS{power/async}=="enabled"
    ATTRS{power/control}=="auto"
    ATTRS{power/runtime_active_kids}=="10"
    ATTRS{power/runtime_active_time}=="0"
    ATTRS{power/runtime_enabled}=="disabled"
    ATTRS{power/runtime_status}=="unsupported"
    ATTRS{power/runtime_suspended_time}=="0"
    ATTRS{power/runtime_usage}=="0"
    ATTRS{waiting_for_supplier}=="0"


I got 2 serial...
Code:
root@pve:/mnt# udevadm info --name=/dev/bus/usb/001/049 --attribute-walk | grep serial
    ATTRS{serial}=="000000000"
    ATTRS{serial}=="0000:00:14.0"
root@pve:/mnt#

Tricky case :-/
 
I tried to start from the beginning:

I plug the key:
Code:
[253457.618475] usb 1-3.1: new full-speed USB device number 55 using xhci_hcd
[253457.758345] usb 1-3.1: New USB device found, idVendor=067b, idProduct=2303, bcdDevice= 4.00
[253457.758359] usb 1-3.1: New USB device strings: Mfr=1, Product=2, SerialNumber=0
[253457.758364] usb 1-3.1: Product: USB-Serial Controller D
[253457.758368] usb 1-3.1: Manufacturer: Prolific Technology Inc.
[253457.767376] pl2303 1-3.1:1.0: pl2303 converter detected
[253457.768576] usb 1-3.1: pl2303 converter now attached to ttyUSB0
[268585.191980] usb 1-3.1: USB disconnect, device number 55
[268585.192198] pl2303 ttyUSB0: pl2303 converter now disconnected from ttyUSB0
[268585.192223] pl2303 1-3.1:1.0: device disconnected
[268585.428290] usb 1-3.1: new full-speed USB device number 56 using xhci_hcd
[268585.568179] usb 1-3.1: New USB device found, idVendor=067b, idProduct=2303, bcdDevice= 4.00
[268585.568189] usb 1-3.1: New USB device strings: Mfr=1, Product=2, SerialNumber=0
[268585.568192] usb 1-3.1: Product: USB-Serial Controller D
[268585.568195] usb 1-3.1: Manufacturer: Prolific Technology Inc.
[268585.577587] pl2303 1-3.1:1.0: pl2303 converter detected

Code:
Bus 001 Device 006: ID 067b:2303 Prolific Technology, Inc. PL2303 Serial Port / Mobile Phone Data Cable
Bus 001 Device 056: ID 067b:2303 Prolific Technology, Inc. PL2303 Serial Port / Mobile Phone Data Cable
Bus 001 Device 003: ID 2109:2817 VIA Labs, Inc. USB2.0 Hub
Bus 001 Device 002: ID 0403:6001 Future Technology Devices International, Ltd FT232 Serial (UART) IC
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
root@pve:/mnt#

Code:
root@pve:/mnt# cat /etc/udev/rules.d/99-usb-prolific.rules
KERNEL=="ttyUSB[0-9]*", SUBSYSTEMS=="usb", ATTRS{idVendor}=="067b", ATTRS{idProduct}=="2303", SYMLINK="ttyUSB9", OWNER="root", GROUP="dialout", MODE="0666", RUN+="/usr/bin/chmod o+rw /dev/ttyUSB9"
root@pve:/mnt#

Code:
crw-rw-rw- 1 root dialout 188,  0 Oct  9 12:16 /dev/ttyUSB0
lrwxrwxrwx 1 root root          7 Oct  9 12:16 /dev/ttyUSB9 -> ttyUSB0
root@pve:/mnt#

On my CTX:

Code:
root@nad:~# ls -l /dev/
total 0
crw------- 1 root   tty     136, 0 Oct  8 20:35 console
lrwxrwxrwx 1 root   root        11 Oct  8 20:35 core -> /proc/kcore
lrwxrwxrwx 1 root   root        13 Oct  8 20:35 fd -> /proc/self/fd
crw-rw-rw- 1 nobody nogroup   1, 7 Oct  6 07:40 full
lrwxrwxrwx 1 root   root        12 Oct  8 20:35 initctl -> /run/initctl
lrwxrwxrwx 1 root   root        28 Oct  8 20:35 log -> /run/systemd/journal/dev-log
drwxrwxrwt 2 nobody nogroup     40 Oct  8 20:34 mqueue
crw-rw-rw- 1 nobody nogroup   1, 3 Oct  6 07:40 null
crw-rw-rw- 1 root   root      5, 2 Oct  9 16:12 ptmx
drwxr-xr-x 2 root   root         0 Oct  8 20:35 pts
crw-rw-rw- 1 nobody nogroup   1, 8 Oct  6 07:40 random
drwxrwxrwt 2 root   root        40 Oct  8 20:35 shm
lrwxrwxrwx 1 root   root        15 Oct  8 20:35 stderr -> /proc/self/fd/2
lrwxrwxrwx 1 root   root        15 Oct  8 20:35 stdin -> /proc/self/fd/0
lrwxrwxrwx 1 root   root        15 Oct  8 20:35 stdout -> /proc/self/fd/1
crw-rw-rw- 1 nobody nogroup   5, 0 Oct  8 10:10 tty
crw--w---- 1 root   tty     136, 1 Oct  8 20:35 tty1
crw--w---- 1 root   tty     136, 2 Oct  8 20:35 tty2
c--------- 0 nobody nogroup 188, 0 Oct  8 16:38 ttyUSB0
crw-rw-rw- 1 nobody nogroup   1, 9 Oct  6 07:40 urandom
crw-rw-rw- 1 nobody nogroup   1, 5 Oct  6 07:40 zero
root@nad:~#

I tried to change rights:

Code:
root@nad:~# chown 100000:100020 /dev/ttyUSB0
chown: changing ownership of '/dev/ttyUSB0': Invalid argument
root@nad:~#

When I tried to access via my script to /dev/ttyUSB0:

Code:
root@nad:~# python3 /root/nad-rs232-rest/nad-rs232-rest.py
2025-10-09 16:13:16,615 - INFO - Starting mqtt thread
2025-10-09 16:13:16,618 - DEBUG - [MQTT] Connected to broker (result code 0)
2025-10-09 16:13:16,618 - INFO - Starting serial port thread
2025-10-09 16:13:16,621 - CRITICAL - [SERIAL] Could not open /dev/ttyUSB0
 * Serving Flask app 'nad-rs232-rest'
 * Debug mode: off

No luck so far, if you have an idea.