Boot freenas/truenas off USB key without bios support

[rdmitry0911]

Hi guys, I have an old computer which I was using for a long time as a FreeNAS server. According to recommendations, I decided to change my boot pool from usb sticks to usb external SSD disks, like this one The problem is that BIOS does not see these devices and can't boot from them, however, if I include in a boot pool a regular usb stick, the system boots fine and FreeNAS sees all devices in a boot pool. I don't like this solution, as in case of fault of usb stick I will not be able to boot the system at all. I thought I can boot gptzfsboot via pxe and after that it continue normal booting itself, but it turned out gptzfsboot does not see these devices either. I also thought if I can make a sort of RAM disk with minimal boot staff and pxe boot it, then it would be possible to remount a root path and continue normal boot process. But I don't know how to make it. With linux it is possible to use plop to solve the same problem, but it turned out, plop doesn't boot FreeNAS boot pool. What can I do to make my system to boot from my new devices? Any help would be very much appreciated
Thank you, Dmitry

 

[rdmitry0911]

Hi guys, using this method I managed to boot the system over PXE, initialize USB dongles and after reboot -r the system start booting from my dongles. The only drawback of this method is that I have to load the kernel and all kernel modules from a RAM disk. That means, that after any TrueNAS update I have to rebuild the ROM disk with new kernel modules and/or new kernel. May be there is a way to modify gptzfsboot to let it see the dongles?