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* Joseph <syscon780@×××××.com> [140905 13:37]: |
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> On 09/05/14 13:12, Todd Goodman wrote: |
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> >* Joseph <syscon780@×××××.com> [140905 12:14]: |
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> >> How to set a boot flag on sda1. |
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> >> I'm using fdisk from util-linux 2.24.1 and in order to set it I need version 2.22 or earlier |
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> >> |
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> >> -- |
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> >> Joseph |
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> > |
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> >If you're using GPT partitions then you should really be using gdisk or |
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> >recent parted (gparted.) |
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> > |
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> >You'll see strange results if you use fdisk to look at GPT partitions (for |
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> >some definition of strange and depending upon if a hybrid configuration |
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> >is used.) |
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> > |
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> >Todd |
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> |
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> Yes, it make more sense. |
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> |
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> Will old BIOS boot GTP partition disk. |
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> My system does not recognize boot sector. It thinks there is no disk. |
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> I can boot current disk with Systemrescue CD but BIOS does not see my boot sector or the way it is installed. |
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> |
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> |
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> -- |
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> Joseph |
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What does 'gdisk -l /dev/sda' say about GPT and MBR (it usually says |
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whether you have a valid GPT and/or MBR before printing information |
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about the partitions.) |
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|
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As others have mentioned, you need that BIOS boot partition for GRUB2 to |
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embed its core.img into since there's no post-MBR gap for it to use with |
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GPT. This is different than the partition you mount as /boot. |
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|
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Your BIOS should be able to boot GPT drives but it can be flaky |
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depending upon motherboard in my experience. |
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If using GPT drives to boot with BIOS you want a protective MBR which |
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encompasses the entire drive (or first 2.2TB if the drive is larger than |
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that as that's as big as MBR can handle.) It has type 0xee. |
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|
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You can create that gdisk (by going into the eXpert menu) or you can use |
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fdisk to create it. |
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|
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With some motherboards you have to flag the protective MBR as bootable. |
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You can do this in fdisk with the 'a' command or in gdisk with the 'a' |
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command on the eXpert menu. |
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|
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grub2 should have installed the correct target by default (i386-pc) but |
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you can force that with the --target command line option to |
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grub2-install ('grub2-install --target=i386-pc /dev/sda' for example) |
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|
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So barring a really strange BIOS implementation you should be able to |
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boot a GPT partitioned drive on a BIOS-based computer but I have to ask |
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why you want to go through all the head-banging? |
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Since your BIOS isn't cooperating the only reason I could see is if your |
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drive is larger than 2.2TB (quite possible but I don't remember from |
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earlier in the thread.) |
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|
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Todd |
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