Sunday probably not the best time to get IT bods on here, but who knows. What’s the best freeware for wiping a disk?

format C:

CCleaner – although I would physically destroy the drive if you’re getting rid of it.

DBan – http://www.dban.org/

I would physically destroy the drive if you’re getting rid of it.

Sending it in for warranty. I’m fairly confident they won’t be doing any forensic techniques, so writing zeros will be sufficient – but I need SW to do that.

Thanks for the tips.

I should probably have mentioned that I only want to nuke a couple of partitions and leave the restore partition unchanged (makes it rather easier to do a restore that way) – so dban appears to be out. I’d really like to do a bit more than ccleaner does as well.

DBAN every time.

Edit: ahhh dban out on the edit. Though personally I’d still nuke it all and rebuild.

DBAN every time.

But it appears to want to nuke the whole disk, not just the partitions I want to – am I missing something? Would really much rather keep the restore partition rather than rely on my USB backup being OK.

Anybody know anything about http://www.diskwipe.org/ which seems to do what I want?

In Disk Utility on Mac OSX, there is an option to erase the disc thirty five times, which ought to be safe. 😀

It also has an option to do a 7-pass erase which apparently meets the US DOD standard for magnetic data erasure.

I woon’t imagine anyone being able to access owt on it after a 7-pass erase, let alone a thirty five pass erase…

Do you need extra software on a PC to do this type of thing? I have erased and reformatted a few HDs for PCs using my Mac, either in one of the internal HD bays or in a FW or USB caddy. But coon’t find anything that did the same on the PC.

The issue elf is that I need something which will boot from a USB key – one of the partitions I want to wipe is the system one (and I don’t want to take the HD out of a laptop before returning for warranty). I don’t suppose your OSX utility would be a lot more helpful!

…I’ve remembered I have Ubuntu I can boot from a USB stick – I don’t suppose that has a utility to do this?

Elf: yeah that’s what DBAN does. 7 pass, 35 pass, random write etc

Confused tho – what’s the point in wiping one partition for security if you leave a backup partition intact (presumably with a copy of all your data) ?

what’s the point in wiping one partition for security if you leave a backup partition intact (presumably with a copy of all your data) ?

It’s a restore partition, not a backup partition – restores my HD to factory default. I’m very confident it has no user data on.

Look, they’ve all seen pron before, so unless you’ve got some particularly unsavoury stuff on there, what are you worried about?

You jolly well have not got any particularly unsavoury stuff on there have you? I bloody hope you jolly well have not… 😡

Just send it in without the drive and a note explaining that there’s confidential data on it. Not uncommon, and if you’re lucky they’ll just whack a new drive in anyway and send it back to you.

Since they’ve seen it all before, you must have something pretty dodgy on it! Incidentally, if you access the drive in Mac OS (USB caddy, maybe?), you can do a secure erase of individual partitions.

<sigh> no not pron – strangely enough that’s not the only thing you might not want other people to see. Does nobody else have confidential stuff other than pron?

Does nobody else have confidential stuff other than pron?

Deathly silence…

(Shuffles feet. Coughs nervously. Whistles in a nonchalant manner)

If you know where the sensitive data is then deleting it and then running ccleaner with one of the secure deletion options should be sufficient. Then run ccleaner’s free-space deletion, again with the secure option. If you don’t know where it is then as you say you’ll have to get something on a USB key. Maybe another option is to restore from your restore partition then nuke the free space with ccleaner?

Maybe another option is to restore from your restore partition then nuke the free space with ccleaner?

That should work, thanks.

Oh, and don’t forget to put a copy of the ccleaner installer on to a USB stick or something before you restore!

If you want to wipe it to reuse it, just format it. If you want to wipe it securely before disposal, DBAN is your bunny.

For the purposes of sending it in for warranty, either of these should be fine. If you kill all the partitions they’ll do a ‘software reload’ on it to restore both your factory install and the recovery partition; chances are they’ll do that anyway, I wouldn’t rely on it coming back with any data on it. If you don’t and just format it, that should be sufficient to stop the RMA monkeys away from your pron collection.

The third option, of course, would be to run the restore from your recovery partition and knock it back to defaults yourself. That should overwrite your old partition to make it sufficiently irrecoverable for all practical purposes. It won’t be to MoD standards but unless you’re worried about becoming the next Gary Glitter you’ll be fine.

Option 4 – send it back without the hard disk in.

[video]http://www.youtube.com/watch?v=yd_O7-rqcHc[/video]

to be sure

The video above is correct. Failing sectors are copied then marked as bad at the hardware level, over time this leads to quite an amount of data that can never be wiped by software, but can be read with suitable specialist hardware.

I doubt that such specialist hardware is likely to be found at the back of PC World. I’d be surprised if more than half of them could spell it, never mind use it.

Why would you think such a thing, Cougar? Based on what information?

IPA?

If you don’t and just format it, that should be sufficient to stop the RMA monkeys away from your pron collection.

I’m paranoid. I’m sure I haven’t got anything incredibly sensitive on there, but I can see the scenario where I don’t get my HD back (and somebody else gets hold of it, in which case a format isn’t good enough).

Maybe I should just trust the recovery USB stick I’ve made? In theory I should be able to DBAN and then use that to get to factory default, but I mentioned above I’m paranoid didn’t I? It just seems it really shouldn’t be all that difficult to wipe partitions rather than the whole disk, but I can’t find an appropriate self-boot tool.

linux distro + shred ought to do it

http://www.techrepublic.com/blog/opensource/securely-delete-files-with-shred/188

use shred.. then take the reference to the partition out using a partition editor .. such as GPARTED

Why would you think such a thing, Cougar? Based on what information?

The former based on the idea that they’ve no reason to have it. The latter based on comedic licence.

I’m paranoid

Pull the disk before you send it back. everyone’s a winner.

What#s up with it, anyway?

The computer’s locking up (very intermittent – can go a week or more fine, then lock up several times in a day) – the first suggestion of the techie was a disk problem, so I’m reluctant to cause myself added hassle (why didn’t you send in the bit we think might be faulty?) for a warranty claim. I also need to prove it happens with a fresh install, and would like to send it in straight after it’s locked up, hence want a working install with a clean disk.

Right now I’m running Ubuntu from a USB stick, running
dd if=/dev/zero of=/dev/sda2
Not the most robust method, but as I said up there I’m happy writing zeros to the partition – people get overly worked up about multiple passes, given that having written zeros once you won’t get any data off without dismantling the disk, and I’m really not expecting anybody to do that. Not like I have anything really sensitive on there, but I’d rather somebody who got hold of the disc couldn’t read my personal letters, bank account details etc. just by using a hex editor on the partition (as I am right now in Ubuntu to check the wipe is working – it’s surprisingly easy to get stuff off if you don’t wipe at all, and surprisingly hard after a single write of zeros).

I was going to use linux ‘wipe’, but found it a lot slower than writing zeros – ‘shred’ doesn’t appear to work on a whole partition, just individual files, hence leaving the signature of anything I’d already deleted.

Anyway, thanks for the help folks.

‘shred’ doesn’t appear to work on a whole partition, just individual files

yeah the intention was to do all files on the partition, then [optionally] format the partition. Then delete the partion in GPARTED. This isn’t going to be as good as running DBAN on the disk though. Depends how paranoid/worried you are.