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>> dd is pretty thorough... afterall, it writes to every single block on the |
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>> disk. |
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>> |
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> |
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> And the resulting effect from doing that once is: |
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> |
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> Trivially easy to recover the data that was there just before you did the dd |
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> |
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> Why? Data on-disk is not a binary cell like ram. It is a magnetic pattern and |
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> the pattern from the previous write is still there IIF you know how to find it |
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Agreed, using all zeros will just change the magnitude of the field, |
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which will make it more difficult to read, but the underlying data will |
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largely remain. You should use random data so with dd you could use |
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if=/dev/random but that would be horribly slow so maybe if=/dev/urandom. |
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But why bother when there's a tool like shred. I boot a Knoppix cd then |
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use it on the raw device as i cant see any point in doing each partition |
| 18 |
separately. |
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