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On 06/09/2014 04:10, Joseph wrote: |
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> On 09/05/14 21:02, Joseph wrote: |
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>> I'm configuring MBR partition for older disk and need to know what |
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>> code to enter for boot partition. |
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>> My BIOS is not EFI type. |
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Not that it particularly matters but a partition dedicated to /boot |
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contains a Linux filesystem and, thus, 83 is appropriate. |
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> |
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> My current configuration: |
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> fdisk -l /dev/sda |
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> |
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> Disk /dev/sda: 447.1 GiB, 480103981056 bytes, 937703088 sectors |
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> Units: sectors of 1 * 512 = 512 bytes |
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> Sector size (logical/physical): 512 bytes / 512 bytes |
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> I/O size (minimum/optimal): 512 bytes / 512 bytes |
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> Disklabel type: dos |
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> Disk identifier: 0x021589e5 |
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> |
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> Device Boot Start End Blocks Id System |
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> /dev/sda1 * 2048 155647 76800 83 Linux |
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> /dev/sda2 155648 4349951 2097152 82 Linux swap / Solaris |
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> /dev/sda3 4349952 937703087 466676568 83 Linux |
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> |
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> Does the sda1 has to start with "1" or 2048? |
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As of util-linux-2.18, partitions are aligned to 1 MiB boundaries by |
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default, so as to avoid performance degradation on SSDs and advanced |
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format drives [1]. |
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Further, beginning at 2048 as opposed to 63 (in the manner of MS-DOS) |
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provides more room for boot loaders such as grub to embed themselves. |
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To have the first sector be a partition boundary is impossible because |
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that is the location of the MBR and the partition table. |
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In summary, let it be. |
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--Kerin |
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[1] https://bugs.gentoo.org/show_bug.cgi?id=304727 |
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[2] https://en.wikipedia.org/wiki/Master_boot_record |
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