GEOM: ada0: the secondary GPT header is not in the last LBA or random: unblocking device. when using more than 2 cores

[Nicolas Embriz]

Hello, I have been creating FreeBSD images to use within AWS with ZFS
on root, using this scripts: https://fabrik.red
(https://github.com/fabrik-red/images/blob/master/fabrik.sh)

Recently I created a new image but start to notice that when using
t2.medium or instances with more than 1 core, they are not booting and
in many cases, I get this message:

    GEOM: ada0: the secondary GPT header is not in the last LBA.

of

   random: unblocking device

This seems to be happening only with FreeBSD 11.1 prerelease, with
11.0 is working fine working image can be found here:
https://github.com/fabrik-red/images/releases either with 1 core or
more than 2 cores.

This is the kernel I am using:
https://github.com/fabrik-red/images/blob/master/fabrik.kernel

Any idea of what could be causing this issue?

The pattern I have found is that this only happens with instances with
2 or more cores.

Regards.