So my idea was to use my favorite unix-like system (FreeBSD) with multiple serial ports. For such appliances I usually use Soekris or Alix boards with FreeBSD on Flash. The question is how to have multiple serial (RS-232) ports. The simplest method nowadays is to use usb serial adapters. I know these usb serial converters has some issues but it is really the simplest peace of hardware to buy, plug and play.
When you use some of these USB converters you should see new devices. In my case I see in dmesg following devices:
uftdi0:To make serial console working you have to load uftdi module. uftdi -- USB support for serial adapters based on the FTDI family of USB serial adapter chips.
The easiest way is to load this module during boot. You just need to add to /boot/loader.conf following line
uftdi_load="yes"After next boot you will have following new devices in your /dev/ directory
/dev/cuaU0... and you can use program cu to connect to particular serial console. For example
cu -l /dev/cuaU0 -s 9600to connect to console with speed 9600 bauds.
|Soekris NET4801-48 with USB reduction to 4xRS232|