Boot from one drive and load FreeBSD from another

[Walter Parker]

Hi,

I'd like to boot FreeBSD 12 on a system where the OS is installed to a ZFS
pool that can't be booted by the OS.

This is a pre-UEFI machine. It has a pair of SAS drives and 3 PCIe slots.
What I'd like to do is put the boot loader on the SAS drive and then have
FreeBSD load from a ZFS mirror created using 2 nvme SSD drives on PCIe to
M.2 adapter cards. The BIOS is old enough that it will not boot from a PCIe
card.

If I create a FreeBSD-boot partition on the SAS drive and a FreeBSD-zfs
partition on the ZFS mirror, will the boot partition loader automatically
find the ZFS pool? If not, is there anything special I can do to force a
boot?

Second, if I want to do this on a second machine that does have UEFI, can I
do the same thing? This time, I think would I would do is put a UEFI boot
partition on the SAS drive and have it find the FreeBSD-zfs partition on
the ZFS mirror.


Thank you,


Walter

-- 
The greatest dangers to liberty lurk in insidious encroachment by men of
zeal, well-meaning but without understanding.   -- Justice Louis D. Brandeis