Migrating from UEFI to BIOS Installation?

[ObKnoxious]

Hello,

My new NAS had been operating smoothly for about six months when the motherboard in the system died. Eager to get it back online I got a compatible motherboard and planned to just move all drives and other hardware onto it. I did not realize that this mother does not UEFI boot as an option, and my prior installation was on UEFI. I have confirmed all my drives are still good, the storage disks show up and I was actually able to boot to the shell of my installation disk on my main desktop. I have created a temporary FreeNAS installation on a spare hard drive I had and was hoping to somehow migrate my configuration and ability to view my pools and data from my UEFI SSD and onto this temporary install, before cloning that drive back over onto the SSD, now in BIOS mode. Is this possible? Can I somehow mount my SSD to move the configuration over or clone the SSD without cloning the bootloader? Any help would be appreciated.

Full specification for reference
GIGABYTE GA-990XA-UD3 Rev 1.1 Motherboard
16GB DDR 1333Mhz RAM
FX-6300 Processor
2x4TB Seagate IronWolf storage drives
1x160GB Temporary BIOS based Freenas installation drive
1x120GB SanDisk SATA SSD UEFI based installation drive

 

[Patrick M. Hausen]

You can boot from a rescue/live CD with FreeBSD 12.2 and change partition 1 from UEFI to BIOS boot. Assumed that your boot drive is ada0:

Code:

gpart modify -i 1 -t freebsd-boot ada0
gpart bootcode -b /boot/pmbr -p /boot/gptzfsboot -i 1 ada0

 

[SweetAndLow]

Or just reinstall in bios mode. Then upload config file. You might not even have to upload the config since they store a backup on the pool now

 

[ding0k]

Or just reinstall in bios mode. Then upload config file. You might not even have to upload the config since they store a backup on the pool now

I just did this, but in reverse. I replaced a legacy-booted USB boot disk with a UEFI-booted m.2 nvme SSD. I had to choose UEFI because my motherboard can only boot from nvme over UEFI. When I uploaded my config to restore after installing fresh, it appears that the boot disk is no longer bootable. My guess is that the recovery process actually contains some information about the boot volume?

 

[SweetAndLow]

I just did this, but in reverse. I replaced a legacy-booted USB boot disk with a UEFI-booted m.2 nvme SSD. I had to choose UEFI because my motherboard can only boot from nvme over UEFI. When I uploaded my config to restore after installing fresh, it appears that the boot disk is no longer bootable. My guess is that the recovery process actually contains some information about the boot volume?

No it shouldn't. The config is designed to be uploaded with any new hardware change.