Hard drive wiping checklist

Macintosh Hard drive Wiping procedure

Some Mac models are very time consuming and difficult to disassemble, full of fussy, breakable parts. In certain cases it is best to wipe the system's hard drive in the unit. In this case, most drives are currently wiped in OSX, further development for Linux live environment boot options are needed.

Remember wiping the hard drive will take some time to complete, so you'll want to make sure you have the computer on the testing shelf or in a location you can leave it for a bit. Be sure to let your instructor know the status of the system before the end of the shift.

Please follow the steps below to wipe a hard drive. If you come across problems, such as the system won't boot from CD, you can refer to MacBuild Tips 'n Tricks for troubleshooting.

OSX Netboot

Steps	Notes/Detailed Instructions
Boot from network	Hold down the "Option" key while turning the computer on (Note: using option key rather than "n" prevents the builder from accidentally ending up at a login or desktop screen in more cases). Release the key when you see the boot preferences screen. Select the Globe and --> to boot to OSX.
Use Disk Utility	Select Disk Utility from the bottom tray. Select the system hard drive, and click on the Erase tab. Select Security Options and select the 7 Pass erase, and OK. Click the Erase button.

OSX via External Hard Drive

Boot from external drive	Connect the computer to an external hard drive with the Mac OSX image installed. Power the drive on. Turn on the computer and hold down the Option key. Select the external drive from the boot options menu and continue. Follow the Disk Utility Steps from above to wipe the drive.

Netboot in Target Disk Mode

Steps	Notes/Detailed Instructions
Boot in Target Disk Mode	Hook Mac to power and to a PC via firewire. Attach a keyboard to the Mac and power it on, holding the "T" key for at least 20 seconds to ensure that it boots into Target Disk Mode instead of an OS. Release the key when you are sure the computer is booting correctly.
Boot to Network	Power up the PC and immediately hold down F12 (or whichever key selects Booting from the Network), release the key when the PC shows it is booting from the network.
Start Badblocks	When prompted, on the PC select Hardware Testing, then Disk Testing. The PC will verify the HDD specs and you should hit enter to confirm them. Once the hardware has been verified, badblocks will start and takes a very long time to complete. When it has finished, the PC will display the results of the tests. If the HDD wipe succeeded, press enter on the PC and disconnect the Mac. If the HDD wipe failed, press enter on the PC, disconnect the Mac, and proceed to remove the HDD from the machine.

Ubuntu via Terminal

badblocks	Use a live disk to boot to Ubuntu. Open Terminal and type $ sudo badblocks -wvvf /dev/sda -c 1024 and hit enter. If that command fails as your instructor to help you determine the device name.

OSX via Terminal

diskutil	Boot to OSX using any of the methods above (test and see if recovery mode Command+R works as well). Open Terminal and type $ diskutil secureErase 2 /dev/sda

Documentation Needed

• Live boot CDs for both OSX and especially PPC Ubuntu
• OSX 10.6 Flash Drive options
• Can one run diskutil from OSX recovery mode? If so, no peripherals would be needed

About OSX secure erase

http://support.apple.com/kb/HT3680