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

Mon Aug 24 08:17:14 UTC 2009

On Aug 23, 2009, at 23:18, Carl Chave wrote:

> Did you try booting with the keyboard disconnected from the FreeBSD
> machine?  Perhaps the vidconsole is favored when a keyboard is
> detected?
>
> On a linux box I had, I would get serial output from Grub, lose it
> during kernel load and then get a login once the OS was up, much like
> what you describe.  I had to add a kernel argument to my Grub config
> so the kernel would output to the serial port.
>
> Did you look here:
> http://www.freebsd.org/doc/en/articles/console-server/freebsd.html
>
> I think 7.2 might be what you are missing but I can't check it myself.
>
> On Sun, Aug 23, 2009 at 3:13 PM, Thomas  
> Backman<serenity at exscape.org> wrote:
>>
>> On Aug 23, 2009, at 20:25, Tim Judd wrote:
>>
>>> On 8/23/09, Thomas Backman <serenity at exscape.org> 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
>>>
>>>
>>> Do you use the VGA/vidconsole at all?
>>>
>>> A serial-only device (think soekris, ALIX/WRAP boards) that has no  
>>> VGA
>>> will have different requirements than a serial-only device will.
>>>
>>> Your loader.conf statements are different than mine in the  
>>> definition
>>> that you have more than I do to enable serial.
>>>
>>> My loader.conf just has one statement:
>>>  console="comconsole"  - to feed ALL bootloaders, kernel probing, rc
>>> startup on the serial device.  /etc/ttys defines the login lines.
>>>
>>> Though trial and error, I found when you use a dual-setup:
>>> "comconsole,vidconsole", the first one (comconsole) will get rc
>>> output, and vidconsole won't.
>>>
>>> Of course, you're on 8.0 and I don't run BETAs.  So the 8.0 BETA  
>>> might
>>> still be having com port oddities, plus I noticed your ttys line is
>>> ttyu0, not ttyd0.  Did 8.0 change the serial line device?
>>>
>>>
>>>
>>> To enable a serial-only device in my setups:
>>> /boot/loader.conf:
>>>  console="comconsole"
>>>
>>> /boot.config:
>>>  -D
>>>
>>> /etc/ttys:
>>> # enable serial line, cons25 or vt100, depending if I'm originating
>>> from a bsd or windows box.
>>>
>>>
>>>
>>> Enabling dual-setups should be just the loader.conf change to dual
>>> console.
>>>
>>>
>>> HTH
>>
>>
>> (Sorry for the lack of inline replies.)
>>
>> I do have a graphics card, and ideally I'd like to be able to use  
>> both, but
>> serial has higher priority (with serial access, I can use minicom  
>> on another
>> *nix box and essentially ssh into DDB, and stuff like that - right  
>> now I
>> have to borrow a monitor, and write info down manually if needed,  
>> turning my
>> head back and forth).
>>
>> I've tried lots of combinations of console=, including simply
>> 'console="comconsole"' and/or combinations of that and -D, -h- -Dh  
>> and -P in
>> /boot.config.
>> The extra lines in loader.conf are from the handbook, which says  
>> they're
>> needed to use comconsole_speed. It seems they do the same thing as - 
>> D and
>> -h, though.
>>
>> Oh, and re: /etc/ttys: Yup, it's ttyuX when using uart(4) which  
>> seems to be
>> the default now. Actually, since my last buildworld half an hour  
>> ago I'm on
>> 9.0-CURRENT. ;)
>> Also, I made sure to set flags to 0x10 for the serial port as per the
>> handbook (although I did it using loader.conf, not the kernel  
>> config);
>> before the change, dmesg didn't mention any flags, but it now does.  
>> Didn't
>> help squat, though.
>>
>> "Though trial and error, I found when you use a dual-setup:
>> "comconsole,vidconsole", the first one (comconsole) will get rc
>> output, and vidconsole won't."
>> This doesn't mirror my experience; comconsole and  
>> comconsole,vidconsole
>> appears to be just the same for me. I've never gotten anything  
>> except the
>> boot loader and a login prompt over to the serial line - at least  
>> not at
>> speed/settings that the client is set up to receive.
>>
>> I'm gonna try 9600 bps soon just to be sure it isn't that, but  
>> seeing how
>> many others have mentioned using "-S115200" I doubt it'll help.
>>
>> Thanks/regards,
>> Thomas
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>>

Yes, I tried without the keyboard (with -P in boot.config), but  
apparently it detects the keyboard no matter what (it prints out  
"Keyboard: yes" even though I yanked the power, then the keyboard, and  
then started it up again).

The article appears to be (even according to itself ;) a shortened  
version of the handbook ( http://www.freebsd.org/doc/en/books/handbook/serialconsole-setup.html 
  ), which doesn't work out for me, I'm afraid.

I'm Cc:ing this to the -CURRENT list in case it's something related to  
new changes.

BTW, 9600 bps didn't help. Same thing, only slower.

Regards,
Thomas