Serial console trouble: loader and login works, but no kernel messages

Thomas Backman serenity at exscape.org
Wed Aug 26 14:23:38 UTC 2009


On Aug 23, 2009, at 14:18, Thomas Backman wrote:

> First off: Not subscribed to this list, please make sure to Cc me if  
> you don't reply directly. :)
>
> Anyway, I finally got my null modem cable, and plugged in in between  
> a machine running 8.0-BETA2 and one running WinXP using Hyperterminal.
>
> My settings:
>
> /boot/loader.conf:
> boot_multicons="YES"
> boot_serial="YES"
> comconsole_speed="115200"
> console="comconsole,vidconsole"
>
> /etc/ttys:
> # Serial terminals
> # The 'dialup' keyword identifies dialin lines to login, fingerd etc.
> ttyu0   "/usr/libexec/getty std.115200" vt100   on secure
>
> /boot.config (which is read properly):
> -Dh -S115200
>
> Anything wrong in the above?
> Hyperterminal is set to 115200 bps, 8 bits, no parity, 1 stop bit,  
> and no flow control (if that's the correct translation to English).
>
> On the serial console, I go from the screen with the FreeBSD logo,  
> with single-user options etc. (which works fine), and then nothing,  
> until a login tty pops up (which also works fine). The main, if not  
> only, reason I want a serial console is to be able to use it for  
> single user mode, DDB, and so on.
> All kernel messages, and all rc messages are seen only on the  
> graphics card; the serial console receives nothing but the "/ 
> boot.config: -Dh ...", the logo screen, and then the login screen,  
> during startup and *nothing* at all during shutdown. Also, I'm able  
> to login and use the system both via the serial console and via the  
> graphics card/keyboard... Is this supposed to be? I'm not  
> complaining, I just got the impression it was one or the other.
>
> Any advice on how to get the kernel/rc messages etc. to the serial  
> console (only or as well)?
>
> Regards,
> Thomas
OK, so to rule out any installation-related problems, I booted from a  
bootonly install CD (a May ~5th snapshot of 8.0-CURRENT), with "boot - 
h -S115200". Same thing: bootloader stuff on the serial console,  
kernel messages on the local computer only - and very slowly, at that,  
I'd say about one line a second. You could very easily see the  
characters being written to the screen.

Am I the only one having these problems? It'd suck to buy a rather  
expensive (probably because they're pretty rare these days, plus I had  
to order from abroad) null modem cable and have it be completely  
useless.

Regards,
Thomas


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