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Martins wrote: |
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|
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> |
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>> |
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>> Um, if you do this, you will more than likely destroy the filesystems |
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>> as well, because the new partitions will not line up exactly with the |
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>> old ones. |
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>> |
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>> Anyway I don't think this is the problem. Afterall, WinXP booted |
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>> fine before on this drive with LBA disabled, so something else is |
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>> up. If you already made the right changes to the boot.ini file, then |
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>> I suspect that a "fixboot" from the recovery mode of the WinXP CD |
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>> will be necessary. |
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>> This should not overwrite the MBR, only the boot loader that is at |
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>> the beginning of the windows partition. |
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>> |
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>> -Richard |
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>> |
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>> -- |
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>> gentoo-user@g.o mailing list |
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> |
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> |
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> there is no worry, writing new partition table give it the same values |
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> (partition start, end, type, order) as before and not a single bit is |
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> lost |
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> |
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|
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What I am saying is that this is not possible with fdisk, because fdisk |
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will insist on creating the new partitions aligned on cylinder |
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boundaries, which will have moved in terms of logical sectors. Example: |
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|
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Let's say you want a 100MB partition, or about 200000 512-byte sectors: |
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|
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With non-LBA geometry, the math is 200000 sectors / (63 sectors/track * |
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16 heads) = 198.41 cylinders. Now round down to 198 cylinders and you |
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get 199584 sectors in your partition |
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|
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With LBA geometry, the math is 200000 / (63 sectors/track * 255 heads) = |
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12.449 cylinders. Again, round down to 12, and you get 192780 sectors |
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in your partition. You can round up to 13 and get 208845, but you |
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*cannot* get 199584. Possibly with another partitioning tool that |
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allows you to specify the starting and ending heads as well as |
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cylinders, but not with fdisk. |
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|
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It is *possible* for this to work if you have just one huge partition, |
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or if your partitions happen to end at even multiples of both (63 * 255) |
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and (63 * 16). |
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And just for the sake of accuracy, the cylinder alignment thing is true |
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for all partitions except: |
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|
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- Cylinder 0, head 0 is reserved for the MBR, so any partition starting |
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at cylinder 0 actually starts at head 1. |
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- Logical partitions actually start at head 0, sector 1, because the |
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first sector contains another partition table that points to the next |
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partition. |
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|
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-Richard |
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|
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-- |
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gentoo-user@g.o mailing list |
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