Looks like to setup a 6in4 tunnel, I need a static public IP first, but I don't have that IP.
And you could do a test, let us change the usb host driver, if the problem can't be reproduced anymore, it proves it is a problem on usb host driver.
To change the usb host driver: add dtoverlay=dwc2 in the config.txt for RPI3B+ board.
to check if usb host driver is changed: lsusb -t (it will show dwc2 instead of dwc_otg).
Looks like to setup a 6in4 tunnel, I need a static public IP first, but I don't have that IP.
And you could do a test, let us change the usb host driver, if the problem can't be reproduced anymore, it proves it is a problem on usb host driver.
To change the usb host driver:
add dtoverlay=dwc2 in the config.txt for RPI3B+ board.
to check if usb host driver is changed:
lsusb -t (it will show dwc2 instead of dwc_otg).