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TSX
Jan 15, 2013, 01:22 PM
I want to zero out my HD and I'm in mountain lion. How do I go about doing this?



blueroom
Jan 15, 2013, 01:27 PM
Put ML on a USB flash (8GB), boot from USB (option key) and do a secure erase.
http://osxdaily.com/2012/07/25/create-os-x-mountain-lion-boot-dvd-usb-drive-liondiskmaker/

TSX
Jan 15, 2013, 01:35 PM
Put ML on a USB flash (8GB), boot from USB (option key) and do a secure erase.
http://osxdaily.com/2012/07/25/create-os-x-mountain-lion-boot-dvd-usb-drive-liondiskmaker/

So a secure erase is an option in disk utility im guessing?

blueroom
Jan 15, 2013, 01:41 PM
So a secure erase is an option in disk utility im guessing?

Yep, Erase, Security Options.

It'll take awhile...

charlieegan3
Jan 15, 2013, 01:42 PM
So a secure erase is an option in disk utility im guessing?

This is going to take a long time, be ready to twiddle your thumbs.

TSX
Jan 15, 2013, 02:08 PM
I'm in no rush but thanks for the replys.

dejo
Jan 15, 2013, 02:15 PM
Put ML on a USB flash (8GB), boot from USB (option key) and do a secure erase.
http://osxdaily.com/2012/07/25/create-os-x-mountain-lion-boot-dvd-usb-drive-liondiskmaker/

Couldn't you just boot into recovery-mode (command-R) to get to Disk Utility? Thus, no need to create a bootable flash.

TSX
Jan 15, 2013, 06:12 PM
1 pass,3 pass or 7 pass? And how long will it take for a 1 TB drive.

dastinger
Jan 15, 2013, 06:19 PM
It depends on which type of security you want to implement. If you really want to make sure the data is never recovered ever use the 7 pass option.

Krazy Bill
Jan 15, 2013, 06:21 PM
1 pass,3 pass or 7 pass? And how long will it take for a 1 TB drive.Long enough to grow weary and cancel the erasure about 1/3rd through.

thekb
Jan 20, 2013, 08:39 PM
Put ML on a USB flash (8GB), boot from USB (option key) and do a secure erase.
http://osxdaily.com/2012/07/25/create-os-x-mountain-lion-boot-dvd-usb-drive-liondiskmaker/


Why would this be necessary? Doesn't Disk Utilitity take care of this for you?

Quad5Ny
Jan 21, 2013, 02:12 AM
So a secure erase is an option in disk utility im guessing?

http://img217.imageshack.us/img217/5046/zerop.png

1 pass,3 pass or 7 pass? And how long will it take for a 1 TB drive.

A Zero pass on a 120GB drive takes about a hour at USB2 speeds (33MB/s). A good 1TB HDD today can hit about 130MB/s. So best case is about 2 hours, worst case 8 1/2.

It depends on which type of security you want to implement. If you really want to make sure the data is never recovered ever use the 7 pass option.

While it might have been true sometime in the 70's/80's, it's in no way true today. The density of today's hard disks prevent any recovery after the drive has been Zeroed.

For a HDD all you need to do is a single Zero pass, anything more and your wasting your time. SSD's on the other hand need to have the Secure Erase ATA command sent to them (and this only works if the SSD manufacturer implemented it correctly).
.

dastinger
Jan 21, 2013, 02:01 PM
Didn't know about that. Thanks for the heads up :)

Quad5Ny
Jan 21, 2013, 04:24 PM
Didn't know about that. Thanks for the heads up :)

There's a lot of mis-information spread about the internet on erasing hard drives and recovery of the data. If you have the time, do a Google search for "zeroed hard drive recovery". :p

dastinger
Jan 21, 2013, 09:41 PM
Will do! I was talking mostly based on what OSX itself says (or said?) when describing the different security options available.