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On Tuesday 23 January 2007 19:47, Hans-Werner Hilse wrote: |
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> Did you reboot between changing the partition layout and creating |
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> that new partition (and moving data)? Otherwise the kernel wouldn't |
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> be aware of the new partition layout. Well, if everything you wrote |
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> is correct, that data should have ended up on that former Windows |
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> partition and that partition should now be an ext3 one. But if you |
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> just didn't care and mounted the old linux partition (sdb2 at that |
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> point in time before the new partition layout), copied data and you |
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> _then_ rebooted -- then you would have written your data to a |
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> partition that was only a reminiscence in the kernel's structures and |
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> not |
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> corresponding to what cfdisk wrote to the HD. That would be an |
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> explanation why the next boot failed. |
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> |
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> > When I do "mount /dev/sdb1 /mnt/zaloha" at /mnt/zaloha I see that |
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> > old Windows NTFS partition that I already deleted (There are |
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> > "Program Files", "WINDOWS", ...). I don't understand why (somewhere |
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> > I read that ext3 start writing at the middle of the disk space to |
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> > prevent defragmentation). |
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> |
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> Deleting the partition is something that only affects the boot |
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> sector. Ext3 should in fact have overwritten this with it's first |
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> superblock. So the mkext2fs you issued did definitively hit the wrong |
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> partition. |
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> |
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> So my suggestion is: try "gpart -w ext2,1.5 /dev/sdb" to find your |
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> partition (even better: write back the backup you've made from the |
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> old partition table. Errrm...) |
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Some background here to elaborate on what Hans has said: |
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It looks like when you moved the data onto the new partition, it got |
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written somewhere on the disk. However, the kernel's idea of how the |
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partitions are laid out at that time and what fdisk just wrote to the |
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disk probably don't agree and the kernel had got it wrong.... This does |
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happen when you delete two or more partitions and create one large one. |
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That's the bad news. The good news is that unless you did something to |
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wipe the disk clean, the data is there somewhere and you need to find |
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it. Hans' gpart command will search the disk looking for the sequence |
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of data that is found at the start of a filesystem, and will then make |
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a smart estimate as to what the partition ought to look like. |
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The next good news is that you can create and delete partitions many |
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times and still get the data back intact as long as you don't overwrite |
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it. fdisk updates the partition table right at the start of the disk |
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and does nothing else so you can always undo these changes. Until you |
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are happy that everything is back it will be smart to mount this |
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partition read-only so it can't be changed: |
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mount -o rw /dev/sdb1 /path/to/mount/point |
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You say in your original mail that after moving the data "everything was |
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fine". What exactly do you mean by that: |
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1. The command ended without failure so you assume it moved stuff |
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correctly, or |
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2. You proved the move was done by mounting the partition and all your |
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files were there, or |
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3. Some other reason? |
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alan |
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-- |
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