Question about HD partioning.

[Amiduffer]

On a PC help site, in response to a question of what would fully erase a HD, someone came up with this when I raised the question of just partitioning to erase the HD.

You can, But all it does is wipes the partition table and writes a new one. The HDD still has most of the data on it, The HDD has just flagged all the sectors as being empty - were in fact they still have the data there. It is only gone once the HDD has written over it. When you delete something, where it is located on the HDD its just flagged and the computer says its empty. But its actualy still there, untill written over by other data.

Now, when I've used WBtoolbox, and have partitioned a HD, it warns you that by doing so, everything will be erased. Does AOS handle it differently than on the PC side?

[adolescent]

Nope.  You can easily recover the partition information and the data that is on the disk.

[Piru]

...but the warning is in order. Don't try this at home, kids!


(Yes recovery is possible, but if you can't recover the partition information for some reason, the data is scattered all around the disk, and you have no map...)

[Amiduffer]

Whew! Thats good to know.

If you're going to sell a HD, is your basic WB format good enough to completely erase everything? Or do you need a special program like they do on the PC side?

[orange]

link

[Thomas]

Yes, standard format (not quick) will wipe everything from the partitions. If you have unpartitioned areas which cannot be formatted, then those areas will not be wiped of course. And the partiion table obviously cannot be wiped by format either (unless you create a mount list which contains the first two cylinders).

And be warned that you cannot format above the 4GB bar unless you use the very latest format program of OS3.9 or sfsformat, pfsformat or similar.

However, in a laboratory with the possibility to disassemble the drive and to measure magnetism inbetween the "official" tracks, it would probably be possible to recover at least part of the data. If you search the internet you'll find many success stories from recovery companies who recovered all data from HDDs which were accidentally prepared to be sold.

Bye,
Thomas