Serial Console Help Needed

Jay at
Tue Nov 29 04:19:48 GMT 2005

On 11/29/05, Brian McCann <bjmccann at> wrote:
> Hi all.  I'm having a heck of a time trying to get a serial console
> setup on 5.4.  I've recompiled the boot blocks to set the speed to
> 19200, added "set console="comconsole" " to /boot/loader.rc, turned on
> /dev/ttyd0 and ttyd1 in /etc/ttys, and added -P to /boot.config.  I
> can see the kernel messages, then it looks like when rc runs, it
> stops.  I don't see anything beyond "Mounting root from
> ufs:/dev/da0s1a", until I get my getty (which, for some reason is
> ttyd1, not ttyd0).  The config for sio0 in dmesg shows "sio0:
> <16550A-compatible COM port> port 0x2f8-0x2ff irq 3 flags 0x10 on
> acpi0".
> Any ideas?  I'm out of good ones...
> Thanks,
> --Brian
> _-=-_-=-_-=-_-=-_-=-_-=-_-=-_-=-_-=-_-=-_-=-_
> Brian McCann
> Systems & Network Administrator, K12USA
> "I don't have to take this abuse from you -- I've got hundreds of
> people waiting to abuse me."
>                 -- Bill Murray, "Ghostbusters"

try add nc flag(no carrier) to gettytab entry
like this..

ttyd0   "/usr/libexec/getty serialcon"  vt100   on  secure
(or ttyd1..?)

it fixed same trouble on mine.

btw, I don't know why your sio0 is 0x2f8 irq3 .. isn't it supposed to
be detected as sio1?
If you are going to use boot0sio too, you need to add
'BOOT_COMCONSOLE_PORT=0x2F8' to /etc/make.conf then
recompile/install /sys/boot then install boot0sio using boot0cfg(8).

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