How to connect using serial (usb/com RJ45) port on macOS:

$ sudo cu -s 115200 -l /dev/tty.usbserial-DN04FSAL

To bail out when you’re done, type ~. as you would with SSH.

Boot example:

pfsense boot

After installing (zfs on root):

pfsense setup

The toy:

pfsense fw4a