How does one get a working serial console with gptboot?

Freddie Cash fjwcash at
Wed Mar 16 21:44:20 UTC 2011

On Wed, Mar 16, 2011 at 2:20 PM, Garrett Cooper <yanegomi at> wrote:
> On Wed, Mar 16, 2011 at 10:20 AM, Freddie Cash <fjwcash at> wrote:
>> On Wed, Mar 16, 2011 at 9:49 AM, Freddie Cash <fjwcash at> wrote:
>>> I feel like an idiot right now because I can just not figure out how
>>> to make $subject work on a -CURRENT system.  :(
>>> I've read through the Handbook chapter on this.  I've done the process
>>> I've used with 8.x systems.  But once the kernel loads, the serial
>>> console stops working.  I'm obviously missing a step somewhere.
>>> Here's what I've done.  Please point out my error(s):
>>> /boot/loader.conf:
>>>    hint.uart.0.disabled="0"
>>>    hint.uart.0.flags="0x30"
>>>    console="comconsole vidconsole"
>>>    comconsole_speed="115200"
>>>    boot_multicons="yes"
>>> /etc/make.conf:
>> Nevermind.  PEBCAK error.  Adding the right port address would work.
>> Amazing how easy it is to mixup a 3 and an E.  :(
> Are you referring to the .flags value or the BOOT_COMCONSOLE_PORT value?
> Thanks,


The BIOS is configured to use COM3 for the remote access support, with
an address of 3E8.

The kernel sees COM3 as uart0 with an address of 0x3e8.

Me, in my infinite copy/paste wisdom set loader.conf and make.conf to use 3F8.

Figured that one out by dropping to a loader prompt and reading
through the output of "show" and manually setting the hint.uart.0.port
correctly.  Then setting it in loader.conf and make.conf correctly

Freddie Cash
fjwcash at

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