freebsd stable - Jun 2018 - 11.2-Beta3 fails to boot: legacy mode ZFS

Hello,

Background:
-------------
System was originally installed with an 11.0 CD. At the time I tried to 
get UEFI to work, but ended up booting in legacy/BIOS mode. Upgrading to 
11.1 was uneventful. The system has a single SSD with full disk 
encryption and ZFS. Again, nothing special, just the user selectable 
install options from the 11.0 CD.

Current Failure:
------------------
After running "freebsd-update upgrade -r 11.2-BETA3" the system failed
on reboot. Disk encryption keys can be entered, boot prompt appears, 
boot starts but fails at ZFS. Reboots with no info sent to the console.

Luckily, selecting kernel.old at the boot prompt works fine.

Any ideas? Need more info? What can I do to help track down the bug?

Thank you

-- 
David Samms

04.06.2018 7:59, David Samms wrote:
> Hello,
> 
> Background:
> -------------
> System was originally installed with an 11.0 CD. At the time I tried to get
UEFI to work, but ended up booting in legacy/BIOS mode. Upgrading to 11.1 was
uneventful. The system has a single SSD with full disk encryption and ZFS.
Again, nothing special, just the user selectable install options from the 11.0
CD.
> 
> Current Failure:
> ------------------
> After running "freebsd-update upgrade -r 11.2-BETA3" the system
failed on reboot. Disk encryption keys can be entered, boot prompt appears, boot
starts but fails at ZFS. Reboots with no info sent to the console.
> 
> Luckily, selecting kernel.old at the boot prompt works fine.
> 
> Any ideas? Need more info? What can I do to help track down the bug?
This does not seem to be ZFS problem as kernel tries to mount it after it probes
all other devices
showing lots of info to the console.

You should enable both of loader's verbose loading and kernel verbose boot
and try to capture all output.
Does your system have any COM-port? Both loader and kernel are capable of
duplicating output to serial port.