IPMITool questions:

[Harry Schmalzbauer]

Bezüglich James B. Byrne's Nachricht vom 11.12.2017 20:57 (localtime):
> 
> On Mon, December 11, 2017 13:07, Harry Schmalzbauer wrote:
>>
>> Hello,
>>
>> do you want to establish pre-boot sessions via SoL or a login session
>> to FreeBSD?
>>
> 
> I only need access to the pre-boot console.  The remote system is set
> up with an encrypted zfs file system and configured to boot from zfs. 
> The boot process needs the encryption key pass phrase to start.

That's what I would neither call pre-boot nor post-boot, but during-boot ;-)

Similar solution: You have to tell the boot loader to use serial console.
Out of memory I don't know which stage asks for GELI... If
/boot/loader.conf (3rd stage) is too late (which I don't think, so it's
worth trying boot_multicons="YES" in /boot/loader.conf), you can pass
"-nDS115200" to the 2nd boot stage, by putting it into /boot.config.

Hope that helps,

-harry