My question is in fact related to OS X, however I'm using Linux tools to resolve my problem.

I'm trying to delete all the partitions on my SSD drive and create new GUID (HFS+) partition table. Native Disk Utility is unable to eject disk to re-partition it. From the terminal, which is included in the OS X install, I've ran diskutil and here is the output:

enter image description here

diskutil unmountDisk force /dev/disk0...12 also can't unmount disks.

I've started Ubuntu 12.10 from USB, tried to delete all partitions with GParted (except the recovery partition); it seems to be ok, but the disk is still unavailable for creating partitions with Apple Disk Utility. And certainly I can't create HFS+ partitions in GParted, cause I don't have hfsprogs installed, and there is no way to install 'cause I don't have Internet connection (Ubuntu can't work with Mac Book Retina wifi adapters).

So, the main question is what are these 12 partitions and how to delete them and create one HFS+ partitions?

upad: enter image description here

  • 3
    A simple way to delete the 12 partitions without additional tools is dd if=/dev/zero of=/dev/<disk> – Marco Mar 20 '13 at 22:15
  • @Marco thanks, but I have 12 disks ( one of them is recovery). Should I dd all of them one by one? – Ilya Rusanen Mar 20 '13 at 22:17
  • 1
    I have no clue about MacOS. But from the screenshot the /dev/diskN entries look like disks, not partitions. /dev/disk1s1 seems to be a partition. This might explain the reason you couldn't remove them. – Marco Mar 20 '13 at 22:26
  • @Marco I've updated my post. used df command, it seems these partitions are some kind of mounting points of what? – Ilya Rusanen Mar 20 '13 at 22:29
  • @IlyaRusanen I'm not sure what those are, the last time I used Mac OS X it didn't have all those. But they're not partitions. I'd guess some sort of disk image... If you want to know how to destroy your data with Ubuntu, that's easy (the dd to /dev/disk0 or /dev/disk1 will surely do it)... Maybe Ask Different would be a better place for the Mac OS X-specific part of the question? – derobert Mar 20 '13 at 22:44

Are you sure that /dev/disk2 ... /dev/disk12 are partitions on your SSD? I would expect partitions to have device nodes named /dev/disk1sN, where N is the partition number.

I suggest using the graphical Disk Utility so that you can see what is going on. Better yet, boot to the Recovery Partition (hold ⌘R when powering on) and instead of running the Mac OS installer, launch Disk Utility from the menu. That way, you will be manipulating the partitions before anything gets mounted.


To eject the extraneous disk images use:

hdiutil detach /dev/disk# -force

I've been searching for a way to do this as well - finally found a way.

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