Re: Running headless

Andreas Koppenhoefer (
Sat, 15 Jul 1995 12:45:14 +0200 (MET DST)


> From: Geoffrey Bennett <>
> Subject: Running headless
> Date: Sat, 15 Jul 1995 02:30:35 +0930 (CST)
> I am running a linux box without a video card/monitor at the moment.
> It's working fine (except that it requires a keyboard to boot for
> some unknown reason), but I'm wondering... when things aren't working
> fine, what am I to do then? I've got the serial port connected to
> another box so I can fix things if the ether is down, but I don't get
> kernel messages there, and if the system fails to boot I won't be
> able to figure out why.
> So I guess I've got two questions... 1) how do other people deal with
> this problem? and 2) are there patches available to the kernel so I
> can have a serial console?

I havn't tried something like this yet, but I'm planning to do
so. Here is what I've found out.

- lilo can be configured to send boot messages to serial line, too.

- linux cannot redirect console to serial line, yet. But there are
some hooks which make that possible. In linux/drivers/char/console.c
you can find a call
which registers system console as output channel for printk's. Now if
someone writes a serial_print() function which gets activated by some
lilo argument like
then kernel should initialize tty02 (COM3) as serial console with 2400
baud, no parity and 8 bits. Syntax is taken from lilo's serial

One could think of further capabilities like redirecting to parallel
port connected to a harcopy printer like the old decwriter on an VAX
11/780 with
for using lp1 (LPT2).

- - Andreas
- --
Andreas Koppenhoefer, Student der Universitaet Stuttgart, BR Deutschland
prefered languages: German, English, C, perl ("Just another Perl hacker,")
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