Updating a 12.1 system

Hi,

I am trying to update a system from 12.1 to 13.1 the traditional way:

make buildworld
make kernel
reboot
mergemaster -Fp
make installworld
... and crashes.

Twice it failed during the installworld. I could see no evidence of the
problem in the VM server.

Twice the installworld tried to initiate a reboot but had messed up the
kernel so the boot would hang not finding the kernel.

I have used that same procedure to update kernels hundreds of times, I
have already converted 5 systems from 12 to 13.1 without a problem. The
only difference is that machine is using a 32 bits kernel for historical
reasons. Could that be the probolem?

TIA,

Olivier
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