On Sun, Apr 13, 2014 at 11:08 AM, Jonathan Callen <jcal...@gentoo.org> wrote: > On 04/12/2014 08:19 AM, Tom H wrote: >> >> You can have a gpt partition table with BIOS but if you want to boot from >> that disk, you need a >> bios_boot partition (which the OP has) for grub to embed a binary. > > Technically, I don't think you need a bios_boot partition if you leave enough > space between the > partition table and the first partition (I don't recall having a problem when > my first partition > started 2048 sectors (1MiB) into the disk).
You're correct if you're talking about an msdos-labelled disk with bios firmware because having the first partition start on 2048 as it does now rather on 63 as it used to because the post-mbr gap will always be big enough for grub to embed core.img. But on a gpt-labelled disk with bios firmware, there's a <something> mbr into which grub embeds boot.img but there's no post-mbr gap. So a bios_boot partition's needed in order to embed core.img (IIRC parted calls it grub_bios or bios_grub).
