what should uname -v be telling me here?

Lowell Gilbert freebsd-questions-local at be-well.ilk.org
Fri Jun 27 21:22:04 UTC 2014

paul beard <paulbeard at gmail.com> writes:

> On Fri, Jun 27, 2014 at 1:36 PM, Polytropon <freebsd at edvax.de> wrote:
>> You need to find out where /boot resides (in my case,
>> it's on ad4s1a, which is mounted at /) to identify the boot
>> device (or to be precise, the device the kernel has been read
>> from).
> I keep thinking this should be something you ought to be able to
> discover without being on console. I realize the BIOS can't be
> interrogated but if I knew that the active kernel was ad3:/boot/kernel
> or ad2:/boot/kernel, it would be useful. Kind of surprised that
> doesn't appear anywhere in dmesg or that it can't be read out of
> somewhere.

The boot procedure has to load and boot the kernel without having the
kernel available to create the device nomenclature. [Kind of obvious,
if you think about it.] So interrogating the firmware is the only way
the kernel *could* know where it was booted from. That's impossible 
in the BIOS world, and even if there were a table indicating it in an
ACPI table, that would only tell you which disk the bootloader came
from, which isn't necessarily where the kernel came from.

More information about the freebsd-questions mailing list