I went through a lot of articles on how to create bootable os x install partition but eventually I ended up with a need of making resize of my system partition - unfortunately DiskUtility shows this option greyed out. Any ideas why? I don't want to loose my existing system installation.

DiskUtility window screenshot

Properties say that it is a physical volume and it's not using CoreStorage. This is the output of diskutil list command:

diskutil list

And it seems like I managed to resize this disk0s2 partition with:

diskutil resizeVolume disk0s2 480GB

command. Still don't get why this option is absent in DiskUtility. It used to be there. And unfortunately this is not what I was looking for. After I resized this volume DiskUtility didn't allow me to create a new partition. Therefore I think the problem is in that I didn't partition drive properly from the very beginning. diskutil splitPartition doesn't work at all - it says that it cannot unmount disk. Any ideas other than to wipe HDD contents out and install from scratch? I don't want to install Snow Leopard first and update it to El Capitan. enter image description here

1 Answer 1


Try to return everything back:

diskutil resizevolume disk0s2 R

and then:

diskutil resizeVolume disk0s2 480G jhfsx InstallOSX 10G

Resizing a volume that is currently set as the computer’s startup disk will invalidate that setting; use the Startup Disk System Preferences panel or bless (8) to reset the resized volume as the startup disk.

  • I will try it this evening when I get to home.
    – Zorgiev
    Apr 25, 2016 at 8:40
  • I removed the 1! The resizeVolume (in contrary to the splitPartition) verb doesn't require a numberofPartitions.
    – klanomath
    Apr 25, 2016 at 13:11
  • Yes, this command works fine. I managed to extract InstallESD.dmg to this partition, but it doesn't seem that it is bootable. How can I make it bootable?
    – Zorgiev
    Apr 25, 2016 at 19:32
  • @cave-canem I have chosen recover from image to extract InstallESD to this partition. It's of hfs+ type now. But it is not bootable.
    – Zorgiev
    Apr 25, 2016 at 19:50
  • I do not quite understand what it means to "make a bootable InstallESD"
    – cave-canem
    Apr 25, 2016 at 23:54

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .