How Can I Configure Udev Rules To Dynamically Assign Persistent Device Names To A Set Of Identical USB-attached Serial Console Devices From Different Manufacturers, While Also Ensuring That The Device Names Are Correctly Reflected In The System's /dev Directory And Preserved Across Reboots, Even When The Devices Are Hot-swapped Or Disconnected?

by ADMIN 347 views

To configure udev rules for assigning persistent names to USB-attached serial console devices from different manufacturers, follow these steps:

  1. Identify Device Attributes:

    • Plug in each device and run lsusb to find their VID, PID, and serial number.
    • Use udevadm info -a --name=/dev/ttyUSBx (replace x with the device number) to get detailed attributes.

  2. Create udev Rules:

    • Open a text editor and create a new file in /etc/udev/rules.d/, e.g., 99-serial-consoles.rules.
    • For each device, add a rule using attributes like VID, PID, and serial number. Example:
      SUBSYSTEM=="tty", ATTRS{idVendor}=="1a86", ATTRS{idProduct}=="55d4", NAME="/dev/console1"
      Replace VID, PID, and name with your device's specifics.

  3. Reload udev Rules:

    • Apply the new rules without rebooting by executing:
      sudo udevadm control --reload_rules

  4. Test Configuration:

    • Unplug and replug each device to trigger udev.
    • Check the device names in /dev and verify with dmesg | tail to ensure correct naming.

  5. Ensure Persistence:

    • After confirming the names are correct, reboot the system to test if names persist.
    • Hot-swap devices to ensure names remain consistent.

This setup ensures each device has a unique, persistent name, making it easier to manage and reference them in applications.