MacOS – Unable to Extend Macintosh HD partition to use Free Space

disk-utilitydiskutilmacospartition

After a failed Linux installation I'm unable to extend my Macintosh HD logical volume to recover unused space. I'm on v10.12.6 of macOS Sierra. Trying to remove the "Free space" partition in Disk Utility results in a message of

The requested size change for the target disk or a related disk is too small. Please try a different disk or partition, or make a larger change.

Since it's a ~20GB change I'm not sure that's the problem. I've tried using the Disk Utility First Aid tool on the physical disk and logical volume.

I'm nervous about using the diskutil coreStorage resizeVolume command since a) it doesn't seem to use the /dev/disk0s2 identifier and b) I've read that it's unsupported (but does show up in diskutil coreStorage on my version of macOS).

Attached are the Disk Utility and diskutil list output for more info.

disk util window
diskutil list

Best Answer

Try booting from recovery or install media and following the same procedure. Usual caveat: make a full backup of things just in case.

I've had the same situation as you and it worked for me, the only difference was my drive was Time Machine rather than a boot volume. The route I took was make a bootable USB drive with DiskmakerX[1] rather then in-built recovery partition on the Mac.

[1] http://diskmakerx.com

Related Solutions

MacOS – How to Add Free Space to a Logical Volume Group

You can't move the start block (=380677208 for LVG2 or "Macintosh HD 2" in your case) of a CoreStorage Volume (Group) non-destructively. The same is valid for non-CoreStorage partitions with on-board tools. AFAIK for the latter only iPartition and gparted work. Therefore you can't easily reclaim empty space with a lower start block and an arbitrary size and add it contiguously to existing CoreStorage or non-CoreStorage volumes.

Or with other words: You can expand volumes (CoreStorage or non-CoreStorage) from the ending block to higher block numbers but not from the starting block to lower ones.

You have 2 options though:

Recreating a larger second CoreStorage volume
Creating a new partition in the empty space and adding it as physical volume to your second Logical Volume Group. This will scatter your second Logical Volume Group over several Physical Volumes (PV2 & PV3 - the latter build in the empty space) on the same drive but might be unavoidable if another partition like your Recovery HD or a Data volume exists between LVG1 and immediately before PV2.

Both methods require you to backup/move the content of the second Logical Volume to another volume and its deletion afterwards.

For both methods force-backup all your data.

Then boot to an external thumb drive containing a bootable system or to Internet Recovery Mode (hit altcmdR immediately after the start-up chime)

open Terminal.app in the menubar (Utilities/Terminal)
enter diskutil cs list and diskutil list
enter diskutil cs deleteVolume LV2UUID to delete the second Logical Volume
in your case diskutil cs deleteVolume 976CA58C-E8FF-492A-9968-6FEF64C58A31

Now the 2 different methods divert:

Recreating a larger second CoreStorage volume (recommended):

enter diskutil cs delete LVG2UUID to delete the second Logical Volume Group
in your case diskutil cs delete 4793C4C8-0F56-4673-A2B6-98B15403CD33
Your second Logical Volume Group will be converted to a classical volume with the name "Untitled". This will take some time because it also has to be decrypted.
If you enter diskutil cs list repeatedly you will see the progress of the decryption task (in %).

after the conversion completed enter sudo gpt -r -vvv show -l /dev/disk0*
you have to enter an admin password then
result (some parts omitted):

...
         40       409600      1  GPT part - "EFI System Partition"
     409640    244763224      2  GPT part - "Macintosh HD"
  245172864      1269536      3  GPT part - "Recovery HD"
  246442400(s) 134234808(a)         
  380677208    108287968(b)   4  GPT part - "Untitled"
  488965176      1269536      5  GPT part - "Recovery HD"
...

enter diskutil list
enter diskutil unmountDisk /dev/DiskIdentifierLV (probably disk1) to unmount "Macintosh HD"
enter diskutil unmountDisk /dev/disk0
enter sudo gpt remove -i IndexNumber DiskIdentifier to remove a partition
in your case sudo gpt remove -i 4 disk0 to remove the partition named "Untitled"
enter sudo gpt add -b StartBlock(s) -s NumberOfBlocks(a+b) DiskIdentifier to create a new partition filling the empty space.
in your case probably sudo gpt add -b 246442400 -s 242522776 disk0
enter diskutil list to get the DiskIdentifier of your newly created partition (probably disk0s4)
enter diskutil cs create Name /dev/DiskIdentifier to recreate your second LVG
in your case probably diskutil cs create "Macintosh HD 2" /dev/disk0s4
enter diskutil cs list to get the UUID of LVG2. Copy it.
enter diskutil cs createVolume LVG2UUID jhfs+ Name 100%
in your case diskutil cs createVolume <-PasteTheLVG2UUIDHere-> jhfs+ "Macintosh HD 2" 100%
enter exit, quit Terminal and reboot to "Macintosh HD"
Open "Disk Utility", check the newly created CoreStorage volume "Macintosh HD 2" and quit the app
open the Info window of the volume in Finder and uncheck the box labeled 'Ignore ownership on this volume'.
enable FileVault for the volume/encrypt it
restore "Macintosh HD 2" from your Time Machine backup

Scattered ~~brain~~ PhysicalVolumes method (not recommended but sometimes necessary):

This method is necessary if sudo gpt -r -vvv show -l /dev/disk0 shows following result (some parts omitted):

    ...
             40       409600      1  GPT part - "EFI System Partition"
         409640    244763224      2  GPT part - "Macintosh HD"
      245172864      1269536      3  GPT part - "Recovery HD"
      246442400     83034808
      329477208     51200000      4  GPT part - "Data"         
      380677208    108287968      5  GPT part - "Macintosh HD 2"
      488965176      1269536      6  GPT part - "Recovery HD"
    ...

This partition layout may occur if you have an additional Data partition between your 2 CoreStorage volumes.

enter diskutil list
enter diskutil unmountDisk /dev/DiskIdentifierLV (probably disk1) to unmount "Macintosh HD"
enter diskutil unmountDisk /dev/disk0
enter sudo gpt add -b StartBlock -s NumberOfBlocks DiskIdentifier to create new partition filling the empty space.
in the case above sudo gpt add -b 246442400 -s 83034808 disk0
enter diskutil list to get the DiskIdentifier of the newly created partition (probably disk0s6 - check the size!)
enter diskutil cs list to get the LVG2UUID
enter diskutil cs addDisk LVG2UUID DiskIdentifier to add a physical disk to LVG2
in your case diskutil cs addDisk 4793C4C8-0F56-4673-A2B6-98B15403CD33 disk0s6
enter diskutil cs createVolume LVG2UUID jhfs+ Name 100% to create a new Logical Volume in LVG2
in your case diskutil cs createVolume 4793C4C8-0F56-4673-A2B6-98B15403CD33 jhfs+ "Macintosh HD 2" 100%
enter exit, quit Terminal and reboot to "Macintosh HD"
Open "Disk Utility", check the newly created CoreStorage volume "Macintosh HD 2" and quit the app
open the Info window of the volume in Finder and uncheck the box labeled 'Ignore ownership on this volume'.
enable FileVault for the volume/encrypt it
restore "Macintosh HD 2" from your Time Machine backup

*You don't have to enter 'sudo gpt...' if you are logged in as root (e.g. Internet Recovery Mode)

Windows – get bootcamp to use existing free space on physical disk

More people have problems with BootCamp trying to partition manually than any other way. This is what I would do:

Boot into recovery mode.
Get into disk utility
Delete the partition you created for Windows
Expand your Mac partition all the way into the available space
Now (assuming you already have the BootCamp media created) Run the BootCamp.app and follow the prompts
Part of the process will present you with a graphical representation of your disk and allow you to set as much space as you want for both the Mac and Windows partition.

The thing you have to learn (or un-learn as the case may be) coming from Linux or Windows is that the first thing you should do is nothing. Let the App and/or Operating System do it's thing the way it wants to. Which means things like, "just plug it in," "follow the prompts in the app," or as a last resort read the (usually brief) instructions in the app or on Apple's support web site.

I've been supporting Macs and PCs for 20+ years and it is a whole different mindset. Yes you can tinker, it's just a different method. What you did is not wrong, it just adds unnecessary complications making it necessary to then work around Apple's work-around that they build into BootCamp so you would not have to do all the partitioning manually.

Best Answer

Related Solutions

MacOS – How to Add Free Space to a Logical Volume Group

Windows – get bootcamp to use existing free space on physical disk

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