Also learned yesterday, that the AX.25 port (axports) and the AX.25 interface are NOT NEEDED at all.
Simply start Direwolf, link to D-RATS using a socat command and that works as long as the AX.25 checkbox is checked in the TNC config dialog.
Unfortunately, if you UNCHECK the AX.25 checkbox, this breaks the configuration and the "Radio" will not work.? Still looking for answers on that one.
I am using 0.3.3
