7 Pass Secure Erase

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I started a 7 Pass Secure Erase yesterday at midday and it is still going this morning, so nearly 24 hours now. The status area at the bottom of the disk utility shows Secure Erase. Pass 1 of 7. Estimated time: 6 hours

It's been like that since the start - I can hear some a quiet disk noise so possibly it's doing something.

One guy said this

Well, it took me 1 hour to erase 80GB form a hard drive with a 7 pass eraser, so 2*80*60min/hour*1hour/7passes*35 passes = 600minutes or 10 hours ouch.

It should eb about or around this.

Hope this helps

That was for 35 pass. I decided to do 7 and have 154gb to erase. I feel something's not quite right.

Any suggestions ?

thks
 
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The 6 hours is probably for all 7 passes. And the 1/7 is only telling you what pass you are up to. The speed of the erase would depend on the speed of the computer and the speed of the hard drive in question. Yours might be faster.

So to me it sounds ok.
 

vansmith

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That kind of wipe is going to take a long time and good for those who are paranoid about not being able to recover data. Any particular reason you chose to do this?
 

chscag

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I agree with vansmith. Unless you have extremely sensitive data that you're trying to wipe, a 7 pass secure erase is a waste of time. If your data is that sensitive it would be faster to remove the drive and take a sledge hammer to it instead.

Regards.
 
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The 6 hours is probably for all 7 passes. And the 1/7 is only telling you what pass you are up to. The speed of the erase would depend on the speed of the computer and the speed of the hard drive in question. Yours might be faster.

So to me it sounds ok.

Having done 35 passes before, the time shown is indeed the time for the current pass, not all the passes combined. I had one 400Gb USB 2 drive that took 6 and a half days to run through all 35 passes. Keep in mind that the drives interface plays a role in the speed as well. USB 2 is going to be far slower than an internal IDE or SATA or even a FW 400 or 800 drive.
 
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dsmith2besure
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That kind of wipe is going to take a long time and good for those who are paranoid about not being able to recover data. Any particular reason you chose to do this?

I based my choice on an estimate by another person who said:

Well, it took me 1 hour to erase 80GB form a hard drive with a 7 pass eraser, so 2*80*60min/hour*1hour/7passes*35 passes = 600minutes or 10 hours ouch.

I'm now regretting choosing 7 pass, imagine I nearly went with 35 pass lol

it would be faster to remove the drive and take a sledge hammer to it instead.
- at present I could'nt agree more.

So my main concern is that it's been running well over 24 hours now with no more progress showing than when first started.

I have the option to skip...I wonder what that does exactly ? ? ?

Or leave it going...how long do I do that for ? ? ?

haha
 
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dsmith2besure
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Having done 35 passes before, the time shown is indeed the time for the current pass, not all the passes combined. I had one 400Gb USB 2 drive that took 6 and a half days to run through all 35 passes. Keep in mind that the drives interface plays a role in the speed as well. USB 2 is going to be far slower than an internal IDE or SATA or even a FW 400 or 800 drive.

Ah great someone who's witnessed the time pain before...

it would seem I can add you to the other side (against skipping and be patient)

thks
 

vansmith

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IIf your data is that sensitive it would be faster to remove the drive and take a sledge hammer to it instead.
It's amazing how well that works ;)
 
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Ah great someone who's witnessed the time pain before...

it would seem I can add you to the other side (against skipping and be patient)

thks

Yep. Since it wasn't my primary drive it was no big deal. I just let it run through at its own pace and used my Mac as normal. When it was done I simply started using the drive as normal.
 
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Almost 48 hours now, nothing changed over night.

so has anybody had any experience skipping a 7 pass secure erase ? or even more drastic powering the machine and then trying to do a 1 pass ?
 
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From another forum:

Perhaps I missed something, but has it been established if you are using the security options to erase an entire disk or just to erase free space on it?

I'm trying to erase all data on the disk and wanted to prevent recovery of the disk's erased data so I chose a 7 pass secure erase. I did not choose Erase Free Space I chose Erase after chosing the security option (incorrectly!)

If it is an entire disk, I can't see any real risk in just aborting the process.

Ok that sounds good.

This is based on the following logic: something has gone wrong with the process, which should be writing zero data bytes to the file space at an orderly rate. If that space is an entire drive, then you can just reformat it to recover.

That's what I'm trying to do - reformat but I chose 7 pass secure to write zero's over the data 7 times, now I really understand that really was'nt necessary.

The disk was 154gb full of 160gb. My initial problem began with sporadic slowing down, poor performance. I did a verify disk whilst booted but was unable to complete. So I backed everything up inserted the boot disk and tried a verify from boot disk. This did'nt work either. So I went for the repair, this did not work either but giving me the error Invalid node structure. I tried rebooting normally after this and all I got was a spinning loading symbol and then complete shut down. To confirm this problem I tried to boot again and the same thing happened. I went back to boot from disk and tried verify. This time I received Invalid sibling link. Googled this and found a possible solution by going into terminal and unmounting the volume to repair. This did not work either. I then ran out of options, knowing I had a backup I went to erase all data and re-install osx to start again. However I chose a 7 pass secure erase. That's the story so far. I don't see any flaw in your logic. As long as I can abort this process without damaging the disk then all should be ok and I can do a Zero out, in theory.

If it is an entire disk, I can't see any real risk in just aborting the process.

Great - lets hope just clicking skip does'nt damage the drive...
 
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so I skipped the process which hung then after some time of it not skipping I could'nt quit disk util so I had to power down the machine. I powered it back on and nearly completed a zero out on the disk which hung on creating a partition map something which you would'nt imagine it would hang on yet it did. Had to quit disk util then was able to create partition ok. Re-installation went ok but once installed and booted I noticed real problems navigating around in finder, so I used disk warrior to boot and try to repair the inavlid node structure which I was still getting. I managed to boot disk warrior and do a rebuild. The rebuild was significantly hampered by the hardware, saying that the process was being slowed due to hardware malfunction, not good. Once the report came through It said that it was unable to replace the preview with the original disk, ok, but said that it had fixed any disk problems like node structure, header issues etc. After rebooting I went and did an internal repair which was now saying invalid sibling link... At which point I'd really given up because I had seen this error and tried to fix this in single user mode using fsck with no luck.

So I'm on the hunt for a new internal 2.5 sata hdd, I think preferably to make me feel that I've got something out of all the time I've lost fannying about with the laptop an upgrade is the minimum. Looking at installing this. Have read a few reviews that say no problems with physical size and a fairly simple procedure to replace. I've also read that some people in this posistion have favoured going with an external firewire as the main drive, I just think this is a little pointless having something hanging out the side for a few pounds/dollars less. Anyway just to say thanks for all the replies to this thread. I'll update it again once the drive's arrived and I'm back in my happy place. In the meantime if anyone's got any history with installing a WD 320gb internal into a mbp pro, i'd be interested to hear it.

: )
 

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