On 2026-01-30, Stuart McKim <[email protected]> wrote: > I have a file server that does not have a serial port, only vga. Since > it's normally headless, I'm trying to use a USB serial adapter to > 1. login
that should be possible > 2. display boot messages that will not be possible with a USB adapter > The adapter shows up as: > uftdi0 at uhub3 port 1 configuration 1 interface 0 "FTDI USB Serial > Converter" rev 2.00/6.00 addr 2 > ucom0 at uftdi0 portno 1: usb3.0.00001.0 > > I've been able to test that it's functional by connecting to it from my > desktop, which has a serial port, using: > cu -l /dev/cuaU0 > And all is well. > > Starting with goal 1 (login): > > Trying to add the appropriate entry to /etc/ttys is where I am running > into trouble. First I tried: > ttyU0 "/usr/libexec/getty std.9600" vt220 on secure > > When hitting Enter on my desktop end, I get new lines, but no prompt. > > I changed the entry to: > cuaU0 "/usr/libexec/getty std.9600" vt220 on secure > > Now I get a login prompt, but also receive the following error after > logging in: > ksh: No controlling tty (open /dev/tty: Device busy) > ksh: warning: won't have full job control > > And it's not really a usable session since I don't have a tty. > > What am I doing wrong? It should be ttyU0 not cuaU0 in /etc/ttys. cua is just meant for outbound connections, it allows sharing a single device with tty for incoming connections - see tty(4) for info. It's possible some of the hardware lines aren't connected up, if so and if it's difficult to fix, you could try with 'softcar' and see if that gets you a login prompt?
