RELENG_6: serial console drops back from 115200 to 9600 baud

Dimitry Andric dimitry at
Sun Feb 26 12:28:48 PST 2006

Ed Maste wrote:
> So I suspect that the following happens when you boot:
> - your BIOS sets the serial port to 9600


> - boot0 does nothing with the serial pot

I'm using 'dangerously dedicated' disks, so it's only boot[12] that is used.

> - boot1/2 reads the -P in /boot.config and detects no keyboard, and
>   then sets the serial port to 9600 and the console to comconsole

Indeed, I never got the "/boot.config: -P" message on the serial console
before.  Now I get it, using updated boot blocks.

> - the loader detects that the serial port is enabled and is already
>   set to 9600

> Thus, I'm not surprised that you get a 9600 baud console without
> an rc.conf setting.  The thing that concerns me is your report that
> the console does not run at 115200 even if /boot/loader.conf
> contains comconsole_speed="115200".

This turns out to be an error on my part, sorry to have you worried. :)
I'd accidentally put "console_speed=115200" in loader.conf.  With
"comconsole_speed=115200" and 9600 baud boot blocks, it works okay,
although you don't see any of the boot[12] messages, of course.

That's why installing 115200 baud boot blocks is still the better
solution for me; my BIOS doesn't have any possibility to set the COM
port speeds...

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