Re: [gentoo-user] Re: setting boot flag on sda1

[Joseph <syscon780@gmail.com>]

On 09/05/14 19:57, James wrote:
>Todd Goodman <tsg <at> bonedaddy.net> writes:
>
>> What does 'gdisk -l /dev/sda' say about GPT and MBR (it usually says
>> whether you have a valid GPT and/or MBR before printing information
>> about the partitions.)
>
>gfisk does not seem to be in the tree. That's the old name for the
>"gptfdisk" now in the portage tree. The name is now consistent
>with upstream.  (/sys-apps/gptfdisk)
>
>
>
>> As others have mentioned, you need that BIOS boot partition for GRUB2 to
>> embed its core.img into since there's no post-MBR gap for it to use with
>> GPT.  This is different than the partition you mount as /boot.
>
>> Your BIOS should be able to boot GPT drives but it can be flaky
>> depending upon motherboard in my experience.
>
>> If using GPT drives to boot with BIOS you want a protective MBR which
>> encompasses the entire drive (or first 2.2TB if the drive is larger than
>> that as that's as big as MBR can handle.)  It has type 0xee.
>
>> You can create that gdisk (by going into the eXpert menu) or you can use
>> fdisk to create it.
>
>Maybe gdisk is on the installation iso? It's not in the portage tree, but
>it use to be:
>
>http://sources.gentoo.org/cgi-bin/viewvc.cgi/gentoo-x86/sys-apps/gdisk/?hideattic=0
>
>gdisk and gptfdisk are the use the be the same software..

With a GPT partition and old BIOS 2008 system, I need to set the bootable flag on the protective MSDOS partition. Thats all the BIOS can see.

I need to use an older fdisk and ignore the dire warning about a GPT partition table being detected.

But where to find older fdisk and in stall it from chroot environment.

-- 
Joseph