using your OS disk as a ZIL or L2ARC will never be something you should do(or even can?).
I see. It might not be ideal, but it
can be done if FreeNAS used GPT, this is all I wanted to say.
Anyway, as promised, here are my attempts.
1. Hybrid GPT/MBR
This seemed like the obvious minimal-invasive strategy: leaving the MBR in place and adding just in the GPT an EFI system partition with Grub.
However, in this configuration the Mac Pro wouldn’t offer to boot from USB (i.e., the drive wouldn’t show up in the EFI boot manager)
I remember having read somewhere in the threads dedicated to making Mavericks run on the Mac Pro (what Cainram also mentioned) that someone made it boot from a Hybrid GPT, but who knows.
2. GPT
I just created a fresh GPT with an EFI system partition, formatted it as FAT and mounted it at /mnt/EFISYS, and installed Grub2
Code:
grub2-install --boot-directory=/mnt/EFISYS --efi-directory=/mnt/EFISYS --target=i386-efi --removable
then I created other four partitions with sizes equal to the partitions in the FreeNAS image, and simply used dd to copy the partitions from the image to the stick.
The Mac Pro would allow to boot from this stick and happily load Grub. So far, so good.
Here’s the grub.cfg I used to experiment with:
Code:
insmod part_gpt
insmod part_bsd
insmod ufs1
menuentry 'One' {
insmod chain
set root=(hd0,gpt2,bsd1)
chainloader /boot/loader
}
menuentry 'Two' {
set root=(hd0,gpt2,bsd1)
kfreebsd /boot/loader
}
menuentry 'Three' {
set root=(hd0,gpt2,bsd1)
kfreebsd /boot/kernel/kernel
kfreebsd_loadenv /boot/device.hints
}
It turns out that Grub is able to read the UFS filesystem in (hd0,gpt2,bsd1) (the first partition has a BSD disklabel), so success seemed palpable. However, none of these entries (and the many variations I tried) actually work.
chainloader +1 OR chainloader /whatevs => "error: not a valid root device". I suspect this one works only with MBR
kfreebsd /boot/loader => just hangs.
kfreebsd /boot/kernel/kernel => "error: no symbol table"
I hope this will be of use to someone.