Removed 50GB Linux Partition with Disk Utility and Can’t Boot into macOS

bootcampdisk-utilityhard drivepartitionstartup

For a few years, I've had Linux Mint installed on a 50GB partition on my 2015 MacBook Pro. Today, I decided to remove the installation (I needed the extra 50GB and wasn't using Linux Mint anyway) and used Disk Utility to erase the 50GB partition. After rebooting, I was brought into a minimal GRUB at startup. Rebooting a second time (this time while holding the Option key), there was only an EFI boot option. I decided to go into Internet Recovery mode (using Option Command R) and tried to do a fresh install of MacOS. However, the only partition that was available to install MacOS on was the 50GB partition that I had previously erased.

As it currently stands, my laptop is booting from the 50GB partition (while the other 450GB that had my old MacOS installation cannot be accessed anymore). How would I go about accessing my old MacOS installation and recovering the (hopefully not lost) files?

Best Answer

You need to change the TYPE shown in diskutil list from FFFFFFFF-FFFF-FFFF-FFFF-FFFFFFFFFFFF to Apple_APFS.

The steps below outline one possible way to accomplish this.

Download and install GPT fdisk.
Disable SIP or enter the subsequent commands in macOS Recovery.
Enter the command below to confirm you have the correct identifier for the drive.
```
diskutil list
```

Enter the GPT fdisk command below. If the drive identifier is not disk0, then make the appropriate substitution. If in macOS Recovery, then omit sudo and prepend gdisk with its path (which I believe would be /Volumes/Untitled/usr/local/bin/).

sudo gdisk /dev/disk0

This command is interactive. Enter the values in the first column of the table below.

Entry	Type	Comment
`s`	command	Sort partitions.
`t`	command	Change a partition's type code.
`2`	data	Partition number to change.
`af0a`	data	Hex code for partition type.
`w`	command	Write table to disk and exit.
`y`	data	Confirm you you want to proceed.

If you disabled SIP, then enable.

Related Solutions

MacOS – Disk Utility can’t find free space and Recovery Mode can’t resize

Your EFI is missing in the partition table - the content should be still there though - and the Recovery HD's partition has the wrong type.

To salvage this you just have to rewrite the GUID partition table:

Boot to Internet Recovery Mode
Open Terminal in the menubar > Utilities > Terminal
Enter diskutil list and with the disk identifier of the internal disk found there: gpt -r show diskX. Usually it's disk0 - below I assume it's disk0. Use the disk identifier you have found in your environment in the commands below!
Unmount the internal disk:
```
diskutil umountDisk /dev/disk0
```

Remove all partitions:

gpt remove -i 1 /dev/disk0 
gpt remove -i 2 /dev/disk0

Re-add all partitions:

gpt add -b 40 -i 1 -s 409600 -t C12A7328-F81F-11D2-BA4B-00A0C93EC93B /dev/disk0
gpt add -b 391759648 -i 3 -s 1269536 -t 426F6F74-0000-11AA-AA11-00306543ECAC /dev/disk0
gpt add -b 409640 -i 2 -s 391350008 -t 48465300-0000-11AA-AA11-00306543ECAC /dev/disk0

Verify disk and main volume and repair it if necessary:

diskutil verifyDisk /dev/disk0
diskutil verifyVolume /dev/disk0s2

Resize the main volume:

diskutil resizeVolume /dev/disk0s2 100% #or 250g

Reboot to your main volume

Triple Boot Mac – Solving Boot Load Issues with Mac, Windows, and Linux

As for your first question:

As you probably have already read from the rEFInd web site, the commands. to make rEFInd appear at startup are given below. You would have to enter these commands after booting to the macOS 10.13.2 recovery partition. You could enter the commands while booted to macOS 10.13.2, but you first would have to disable System Integrity Protection.

diskutil  mount  disk0s1
sudo  bless  --mount  /Volumes/EFI  --setBoot  --file  /Volumes/EFI/EFI/refind/refind_x64.efi  --shortform
diskutil  unmount  disk0s1

If the above does not work, then rEFInd is not installed as you described in your question.

As for your second question:

I an not sure why you are worried if the disk utility can recognize your linux partition. Unless you have installed some third party software, macOS can not read linux formatted partitions. Your question gives no indication that you have install such software. Anyway, the output from the diskutil list command shows that the linux partition is being correctly recognized.

If the files on the linux partition are important, then I would think the first priority would be to remove the files from the internal disk. This could be done by creating a a Ubuntu bootable flash drive and boot to a Live version of Ubuntu. If you can access your files, then I would copy the files to a second backup flash drive or other external drive.

Just to let you know:

If you do decide to start over, I would suggest installing the operating systems in the following order.

Install macOS
Use the Boot Camp Assistant to install Windows.
Install Ubuntu using the instructions given here.
(Optional) Install rEFInd.