Accidently created a second partition

Discussion in 'MacBook Pro' started by krzkrzkrz, Jan 5, 2015.

  1. krzkrzkrz macrumors member

    Joined:
    Jul 29, 2010
    #1
    So I was playing around with Disk Utility today. I created a second partition. Format is Free Space.

    How do I undo this? As in, I want to have just one primary partition "Macintosh HD"
     
  2. maflynn Moderator

    maflynn

    Staff Member

    Joined:
    May 3, 2009
    Location:
    Boston
    #2
    Just remove the superfluous partition via the disk utility. You should be able to then extend your Macintosh HD to use up the free space as well.
     
  3. krzkrzkrz thread starter macrumors member

    Joined:
    Jul 29, 2010
    #3
    Thats what I thought. I select the partition. The "-" character is greyed out. As in, it cant be clicked on. I assume thats how you remove it... no?
     
  4. maflynn Moderator

    maflynn

    Staff Member

    Joined:
    May 3, 2009
    Location:
    Boston
    #4
    Try booting into the recovery partition and doing it.
     
  5. yjchua95 macrumors 604

    Joined:
    Apr 23, 2011
    Location:
    GVA, KUL, MEL (current), ZQN
    #5
    Under the Partition tab, click on the partition you accidentally created. Then click the '-' button.

    After that, drag the slider of the original partition back to the bottom to recover space.
     
  6. krzkrzkrz thread starter macrumors member

    Joined:
    Jul 29, 2010
    #6
    Booted with CMD+SHIFT+R then Diskutility. Still doesnt allow me to remove the second partition..

    ----------

    As mentioned earlier. I cannot cilck on the '-' button. It is simply greyed out / unclickable.

    ----------

    In the terminal:


    This is what `diskutil list` returns:
    Code:
        diskutil list
        /dev/disk0
           #:                       TYPE NAME                    SIZE       IDENTIFIER
           0:      GUID_partition_scheme                        *251.0 GB   disk0
           1:                        EFI EFI                     209.7 MB   disk0s1
           2:          Apple_CoreStorage                         125.4 GB   disk0s2
           3:                 Apple_Boot Recovery HD             650.0 MB   disk0s3
        /dev/disk1
           #:                       TYPE NAME                    SIZE       IDENTIFIER
           0:                  Apple_HFS Macintosh HD           *125.1 GB   disk1 <---- I believe, this is the second partition I accidentally created, which I want to remove
                                         Logical Volume on disk0s2
                                         8F5A679C-06AB-44CC-BD46-33E327446D80
                                         Unencrypted
     
  7. Fishrrman macrumors G3

    Joined:
    Feb 20, 2009
    #7
    Here's your "last resort" if nothing else works:

    Use either CarbonCopyCloner or SuperDuper to clone the contents of your "main" partition to an external backup drive. If you use CCC, it will also create a clone of your recovery partition (nice feature).

    Boot from the cloned backup by restarting and holding down the option key until the startup manager appears. Then select the external drive and hit return.

    Once you get booted from the external, open Disk Utility and see if you can erase the entire internal drive, which should wipe out the unwanted partition and leave you with a "one-partition" empty drive.

    Now, launch CCC and "Re-clone" the contents of the backup drive BACK TO the internal drive.

    I realize this seems a roundabout way to get the job done, but sometimes it's the only method that works.
     
  8. Weaselboy Moderator

    Weaselboy

    Staff Member

    Joined:
    Jan 23, 2005
    Location:
    California
    #8
    Here is what I think is going on. You do not have a second partition like you think. You have the one Macintosh HD partition that you somehow shrank then turned into a core storage volume and that is why you cannot resize it into the empty space below. The tipoff is your "free space" comment earlier. That bottom area in Disk Util is not a partition but empty, unpartitioned space left by whatever you have managed to do here.

    Try this. Detach any external drives then enter the command below in Terminal to revert the core storage on the main volume. Wait for that to finish.

    Code:
    diskutil cs revert /
    Now reboot and go back to Disk Util and you should be able to grab the lower right of Macintosh HD and resize it to fill the empty space and apply that change.
     
  9. Fishrrman macrumors G3

    Joined:
    Feb 20, 2009
    #9
    That's a good call by weaselboy above.

    With all the problems folks run into with Core Storage, one would think either Apple or an enterprising 3rd-party developer would come up with a utility dedicated to managing CS in an easy-to-use environment.

    Disk Utility alone does not seem to be enough.
    I sense that Apple is trying to keep folks from having adequate control over CS...
     

Share This Page