New iMac with Fusion Drive issues.

chris's Avatar


27 Dec, 2012 09:23 PM

Just a heads up I guess. I just received a new 27" iMac with the Fusion drive it. I have my 2011 iMac sitting beside it and used CCC as I usually do to clone my current clean OS working drive to an external with recovery partition. All the same procedure I always use for setting up a development or testing machine. However, the new iMac will not boot from any external source. I spent several hours yesterday with different bootable clones created with CCC trying to get the machine to boot. USB, and Firewire (using Thunderbolt adapter) and nothing works. Hold Option and select the clone drive or a recovery partition from the external at you just get the grey circle with a line through it.

Today I tried a thumb drive of 10.8.2, and still nothing. Finailly I booted the new iMac in Target Disk Mode and connected it to the old one, (yes opposite but since I could get it booted I tried this method.) I used CCC to clone the working machine onto the new HD, now I have a shiny new iMac that will not boot at all. Something is not right with these machines and either the recovery/boot volumes created by CCC, or there is just an issue with them period.

  1. 1 Posted by chris on 27 Dec, 2012 10:36 PM

    chris's Avatar

    Well it appears it has something to do with OS X 10.8.2 build numbers. The build number on the 10.8.2 installed on the later 2012 models that are just shipping is likely 12C2034, but the older machines have the App Store version of 12C60. The new machine will not boot from this older version of 10.8.2. I've never actually run across this issue before, and it leaves me stuck with how to get my system setup and data over to the new machine with CCC. Since my development environment I need to move over is more than just my user directory.

  2. 2 Posted by Brian. on 27 Dec, 2012 11:17 PM

    Brian.'s Avatar

    Chris, why not reinstall you special edition of 10.8.2 directly from apple then run migration Assistant on both Mac's to send all the stuff from your old mac to your new one. 2011 Mid Mac mini's had this very same issue when they where brand new, they simply wouldn't take a cloned HD from another Mac the best you could do is try to move stuff over using that assistant tool (or manually copy the home directory/other needed directories without the system files, which is what I did). The reason for these special versions is because they needed different drivers (and a way to know its using the "special version") and the next update you'll be using the same thing as everyone else until then your a bit stuck and copying the files over might be all you need.

    P.S. I could be wrong on what I just said but it worked for me at the time, though I wasn't doing anything with xcode though at the time. I suspect cloning the home directory and uncloning it to the new system would work for 80% of people.

  3. 3 Posted by chris on 27 Dec, 2012 11:22 PM

    chris's Avatar

    What seems to have worked, for now, is that I cloned the old drive onto the new one, thus making it un-bootable. Then I used the internet recovery mode on the new iMac to reinstall OS X on that machine over the cloned one. It appears to have worked fine since I'm typing this on it right now. Everything seems in place. It makes me a little nervous though since I don't like "migration assistant" nor TimeMachine for installing a new system. I like things very clean which is why I used CCC. This does seem to be in order though now.

  4. 4 Posted by Brian. on 27 Dec, 2012 11:24 PM

    Brian.'s Avatar

    Good to hear, I completely understand. Like I said I copied my files myself (from the Terminal). Glad you got this resolved.

  5. Support Staff 5 Posted by Mike Bombich on 30 Dec, 2012 01:29 AM

    Mike Bombich's Avatar

    Hi Chris:

    It sounds like you have this figured out, but for posterity:

    However, the new iMac will not boot from any external source.

    I wouldn't expect it to, and I explain why here in the documentation:

    Use Migration Assistant to move data from an older Mac to a new Mac

    If you clone the new iMac's OS to the external volume, I would then expect the new iMac to boot from the external volume.


  6. Mike Bombich closed this discussion on 30 May, 2013 04:27 PM.

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