It struck me today that using the USB port as a serial device could allow me to do external monitoring of things, so I had a look at the possibility of reading serial input from ttyU0. I can't find any reference to it having been tried, but it seems it ought to be possible.
If it turns out to be possible to receive remote serial data over USB, is it subsequently possible to log it or process it with a script?
Obviously this is the realms of the unsupported, but having an IPSEC capable environmental monitoring box would be really good.
Looking in /var/log/messages for a FTDI,USB or UART shows
Dec 13 00:30:18 badgergateway /kernel: ucom0: FTDI FT232R USB UART, rev 2.00/6.00, addr 4
From the cli, cat /dev/cuaU0 opens the serial port and shows me a stream of incoming serial data at 9.6kbps (It may be possible to negotiate higher since the UART is capable of this). I am reading input data from an Arduino USB port.