Secure Erase SSD on OS X

In preparation for Lion, I planned to do a fresh install & wanted to secure erase my OCZ Vertex 2 SSD to get it working as optimally as possible.  Nothing like a shiny new OS, ridden of all the cruft that builds up over the years.  The problem?  No easy way to secure erase an SSD in a Mac that doesn’t involve using some Windows tool on one of a few compatible SATA controllers that your Mac probably doesn’t have.  It’s possible, but not very easy.  It requires using hdparm & a compatible Linux LiveCD.

You can use *ANY* linux livecd you want, as long as it includes the appropriate graphics card drivers for your model Mac.  I tried several & wound up using PCLinuxOS.  The reason you need the graphics drivers is because you need to be able to suspend the Mac to RAM & wake it back up reliably.  In my experience, this is only easily done if the graphics drivers are installed & I’m not aware of a way to “install” them in a LiveCD while it’s running.  If you can’t get the graphics driver loaded, none of this will work.

I’m not going to repeat all of the instructions for doing the secure erase, as they’re very well documented in the SSD ATA Secure Erase Wiki.  I will go over the process it took me to suspend & wake up my 2008 Macbook Pro, effectively “thawing” out the SSD from it’s frozen state that hdparm reports it to be in.

This assumes you’ve burnt your LiveCD already & it is in your Mac’s optical drive.  Restart your Mac & hold down option to bring up the available boot items screen.  Wait a minute for the optical drive to spin up & you’ll see a disc come up humorously labeled “Windows”.  Hit enter & PCLinuxOS will start booting up.  This can take a while.  Once you’re up & running, you need to suspend to RAM (click Start, Suspend).  The suspend works great, thanks to the right graphics driver being loaded.  There’s a slight glitch resuming, though.  When you resume, the screensaver is going to ask you for a password & I don’t know what it is.  There are two ways to handle this:

  1. Remember to set the password before suspending either using the GUI tool for managing user accounts or the command line tool “passwd”.  I never tried it because I kept forgetting to do it before suspending.
  2. Hit ctrl+alt+f5 to fall back to a root shell & kill the screensaver process (find it by ps -ax), then hit ctrl+alt+f7 to get back to the GUI.

Once you’ve verified the drive is no longer frozen as the tutorial above states, you can then proceed to secure erase the drive.  I successfully did this on my 2009 model unibody Macbook Pro with NVIDIA GPU’s.  I suspect those with ATI *might* have more trouble due to the bad ATI driver support on Linux.

I’ve also found this tutorial after I used this method, which looks like it’s a lot easier, but I have not tried it.

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