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Old 08-16-2005, 12:57 PM   #16
Komakino
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Quote:
Originally posted by Matir
Formatting over a filesystem with the same filesystem should still result in an empty filesystem.

I am at a loss to explain this, other than possibly your new filesystem became corrupted with data from the old filesystem. Are ALL the files gone?
No it shouldn't. Formatting doesn't necessarily remove the files, just sets the disk up to a particular format (for example the reiser filesystem). If you 'change' the format from one fs to the same fs, nothing should be overwritten. As someone previously said, if you were keeping the same fs then the only way you can guarantee that data is wiped is to overwrite every byte on the disk with some value (e.g. 0)
 
Old 08-16-2005, 01:04 PM   #17
tuxdev
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Formatting clears out the references for the files so the files will not show up, but the data would still be mostly intact. It would only be recoverable if you carefully put the right blocks of data together.
 
Old 08-17-2005, 08:43 PM   #18
KimVette
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Quote:
Originally posted by SystemDownfall
1. I believe you are the only one to point this out.
2. You are stupid, I said the files were not there for 3 weeks then reappeared.
3. I'm not an imbecile, I think I notice when I delete a partition and make a new one.
Sometimes when deleting partitions and re-creating them with the exact same configuration you previously had, you will see your old files mysteriously reappear even though you 'deleted' the partition.

The truth is: when you 'delete' a partition you are deleting exactly zilch; you are merely changing the pointers away from that location. When you recreate a partition with the same size, starting at the same point as before, you will end up with the pointers in the partition table pointing at the same structure as previous, and the clusters within that partition will not be changed. So, upon reboot, you may (will) see your files reappear unless you format the partition.
 
Old 08-17-2005, 11:59 PM   #19
Matir
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Quote:
Originally posted by Komakino
No it shouldn't. Formatting doesn't necessarily remove the files, just sets the disk up to a particular format (for example the reiser filesystem). If you 'change' the format from one fs to the same fs, nothing should be overwritten. As someone previously said, if you were keeping the same fs then the only way you can guarantee that data is wiped is to overwrite every byte on the disk with some value (e.g. 0)
I said it would result in an empty filesystem, not an empty partition.

The filesystem's root inode tables would've been re-written, removing any references to the old files.
 
Old 08-25-2005, 01:48 PM   #20
DJOtaku
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It's the same as deleting a file, you're not removing anything, just telling the OS it's ok to write stuff there. Also, it would take rewriting with 1s or 0s quite a few times before it was completely unrecoverable.
 
Old 08-25-2005, 02:25 PM   #21
Matir
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The root inode tables ARE re-written during a format. This does remove references to the children. Formatting does *NOT* remove all data on the disk. It does, however, destroy the root of the filesystem (i.e., superblock). (Because it writes a new one over the old one.)
 
Old 08-25-2005, 04:32 PM   #22
Komakino
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Quote:
Originally posted by Matir
The root inode tables ARE re-written during a format. This does remove references to the children. Formatting does *NOT* remove all data on the disk. It does, however, destroy the root of the filesystem (i.e., superblock). (Because it writes a new one over the old one.)
And there's a backup superblock...so I wonder if somehow he managed to replace the main with the backup??
 
Old 08-25-2005, 07:11 PM   #23
Matir
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The backup superblocks are also re-written by a format. If it happened immediately after the first reboot after reformatting, I'd say the drive hadn't sync()ed or something.
 
  


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