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