MacOS – After Changing Partition Type From FFFF I Can’t Boot

core-storagedisk-utilitymacosmountpartition

I originally asked the following question: Partition Type: FFFFFFFF-FFFF-FFFF-FFFF-FFFFFFFFFFFF Macbook Pro about how to change my partition type from an unknown to a normal one, since it was unmountable.

I was able to and I can now view all of my files, however I cannot boot from it. When I tried verifying it with Disk Utility I received the error:Invalid Disk Label @ 4096: cksum mismatch, and when verifying the partition I get the same error.

After Googling, I found that this was most likely caused by a bad installation of the OS. So I tried to reinstall the latest version of Mac OS Sierra, until the installer said "This disk cannot be used to start up your computer."
Here is all of my info:

sh-3.2# cd /Volumes/Internal/
sh-3.2# ls -la
total 72
      2 drwxr-xr-x   35 root          wheel   1258 Nov  6 22:02 .
  13744 drwxrwxrwt@   5 root          admin    170 Nov 22 11:55 ..
3976587 -rw-rw-r--    1 root          admin  15364 Nov 22 10:53 .DS_Store
 448963 d--x--x--x   10 root          wheel    340 Nov 22 11:52 .DocumentRevisions-V100
4414129 -rw-r--r--    1 root          wheel    591 Nov  6 22:01 .OSInstallerMessages
 458404 drwxr-xr-x@   2 root          wheel     68 Nov 20 16:57 .PKInstallSandboxManager-SystemSoftware
     20 drwx------    5 root          admin    170 Oct  8 13:08 .Spotlight-V100
 498780 d-wx-wx-wt    3 root          wheel    102 Oct  8 18:29 .TemporaryItems
     26 d-wx-wx-wt@   2 root          wheel     68 Nov 22 11:52 .Trashes
3976588 ----------    1 root          admin      0 Jul 30 14:32 .file
     24 drwx------   11 root          admin    374 Nov 22 11:52 .fseventsd
3976589 drwxr-xr-x@   2 root          wheel     68 Nov  6 21:57 .vol
3976590 drwxrwxr-x+ 141 root          admin   4794 Nov 20 18:44 Applications
2719236 drwxr-xr-x    4 root          wheel    136 Oct 29 12:18 EFI
4051944 drwxr-xr-x+  63 root          wheel   2142 Nov 12 12:19 Library
4082330 drwxr-xr-x@   2 root          wheel     68 Nov  6 21:57 Network
3976557 drwxr-xr-x@   4 root          wheel    136 Nov  6 21:53 System
1961160 drwxrwxrwx@  13 Thoughtyness  staff    442 Oct 16 01:28 Twixtor5
1962231 drwxrwxrwx@   9 Thoughtyness  staff    306 Oct 16 01:28 Twixtor5AEManual
 412912 drwxr-xr-x    6 root          admin    204 Nov  6 22:02 Users
 412916 drwxr-xr-x@   4 root          wheel    136 Nov 20 20:58 Volumes
4394376 drwxr-xr-x@  38 root          wheel   1292 Oct 21 04:07 bin
4394413 drwxrwxr-t@   2 root          admin     68 Nov  6 21:57 cores
4394414 dr-xr-xr-x@   2 root          wheel     68 Nov  6 21:57 dev
4394415 lrwxr-xr-x@   1 root          wheel     11 Nov  6 21:56 etc -> private/etc
4415298 dr-xr-xr-x@   2 root          wheel     68 Nov  6 22:02 home
4394416 -rw-r--r--@   1 root          wheel    313 Sep 23 19:18 installer.failurerequests
 434287 dr-xr-xr-x@   2 root          wheel     68 Oct  8 13:44 net
3976539 drwxr-xr-x@   6 root          wheel    204 Nov  6 21:57 private
4395069 drwxr-xr-x@  63 root          wheel   2142 Nov  6 21:56 sbin
4395131 lrwxr-xr-x@   1 root          wheel     11 Nov  6 21:56 tmp -> private/tmp
4395132 drwxr-xr-x@  10 root          wheel    340 Nov  6 22:00 usr
4413886 lrwxr-xr-x@   1 root          wheel     11 Nov  6 21:56 var -> private/var

sh-3.2# diskutil list
/dev/disk0
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *500.3 GB   disk0
   1:                        EFI NO NAME                 209.7 MB   disk0s1
   2:          Apple_CoreStorage                         450.1 GB   disk0s2
/dev/disk1
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:                  Apple_HFS Internal               *449.7 GB   disk1
/dev/disk2
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *31.4 GB    disk2
   1:                        EFI EFI                     209.7 MB   disk2s1
   2:                  Apple_HFS Fixer OS                30.5 GB    disk2s2
   3:                 Apple_Boot Recovery HD             650.0 MB   disk2s3

sh-3.2# gpt -r show /dev/disk0
      start       size  index  contents
          0          1         PMBR
          1          1         Pri GPT header
          2         32         Pri GPT table
         34          6         
         40     409600      1  GPT part - C12A7328-F81F-11D2-BA4B-00A0C93EC93B
     409640  879039128      2  GPT part - 53746F72-6167-11AA-AA11-00306543ECAC
  879448768   97656259         
  977105027         32         Sec GPT table
  977105059          1         Sec GPT header

sh-3.2# gpt -r show /dev/disk1
gpt show: unable to open device '/dev/disk1': Resource busy

sh-3.2# gpt -r show /dev/disk2
     start      size  index  contents
         0         1         PMBR
         1         1         Pri GPT header
         2        32         Pri GPT table
        34         6         
        40    409600      1  GPT part - C12A7328-F81F-11D2-BA4B-00A0C93EC93B
    409640  59662480      2  GPT part - 48465300-0000-11AA-AA11-00306543ECAC
  60072120   1269536      3  GPT part - 426F6F74-0000-11AA-AA11-00306543ECAC
  61341656         7         
  61341663        32         Sec GPT table
  61341695         1         Sec GPT header

sh-3.2# dd if=/dev/disk0s2 count=3 | hexdump
3+0 records in
3+0 records out
1536 bytes transferred in 0.000717 secs (2142485 bytes/sec)
0000000 b1 93 d1 22 ff ff ff ff 01 00 10 00 00 00 1c 02
0000010 af 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0000020 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0000030 00 02 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0000040 00 30 25 ca 68 00 00 00 00 00 00 00 00 00 00 00
0000050 00 00 00 00 00 00 00 00 43 53 01 00 00 00 04 00
0000060 00 10 00 00 00 00 40 00 01 00 00 00 00 00 00 00
0000070 01 04 00 00 00 00 00 00 52 9a 8c 06 00 00 00 00
0000080 52 9e 8c 06 00 00 00 00 00 00 00 00 00 00 00 00
0000090 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00000a0 00 00 00 00 00 00 00 00 10 00 00 00 02 00 00 00
00000b0 72 ab b7 ed 17 41 cc 2a b3 59 3d 7c 06 00 ce 3c
00000c0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
*
0000130 b1 df 08 84 aa 00 41 c7 a3 23 5f b5 72 ae 20 f2
0000140 ec e6 54 9c 1e 60 45 f5 8c fd 27 9d 7c 11 f6 a0
0000150 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
*
0000600

Any ideas on how to boot from this?
My only idea would be to create a second partition, install Mac OS Sierra on that, slowly start copying files and resizing the partition until all of my files would be on the new partition, qt which point I could delete the current one and just use the second one, however I'm sure there's got to be a better way.

Best Answer

Your CoreStorage Logical Volume Group or better: the comprised Logical Volume is missing a proper volume header. Usually the volume header starts at the 1024th Byte of a partition and has a length of 512 Bytes.

With other words: your volume is missing a 3rd block with a content similar to this one:

0000400 48 2b 00 04 80 00 21 00 48 46 53 4a 00 00 01 ff
0000410 d1 98 a4 93 d4 33 8b d5 00 00 00 00 d1 98 88 73
0000420 00 06 07 53 00 01 82 39 00 00 10 00 00 fb 6a 00
0000430 00 c5 1c 55 00 25 73 c7 00 01 00 00 00 01 00 00
0000440 00 0d e2 65 00 3e a2 fb 00 00 00 00 02 20 00 fb
0000450 00 00 00 31 00 06 b9 ef 00 00 00 00 00 00 00 00
0000460 00 00 00 00 00 00 00 31 fb 48 1e a0 6c 47 a2 9f
0000470 00 00 00 00 00 1f e0 00 00 1f e0 00 00 00 01 fe
0000480 00 00 00 01 00 00 01 fe 00 00 00 00 00 00 00 00
0000490 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
*
00004c0 00 00 00 00 00 60 00 00 00 60 00 00 00 00 06 00
00004d0 00 00 0a 00 00 00 06 00 00 00 00 00 00 00 00 00
00004e0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
*
0000510 00 00 00 00 0e 40 00 00 01 30 00 00 00 00 e4 00
0000520 00 00 10 00 00 00 e4 00 00 00 00 00 00 00 00 00
0000530 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
*
0000560 00 00 00 00 11 d0 00 00 01 30 00 00 00 01 1d 00
0000570 00 02 80 00 00 00 72 00 00 13 30 97 00 00 13 00
0000580 00 15 c5 aa 00 00 13 00 00 18 2d 23 00 00 13 00
0000590 00 19 d8 fb 00 00 13 00 00 1b 76 cb 00 00 13 00
00005a0 00 1c 34 70 00 00 13 00 00 1d 0e 4d 00 00 13 00
00005b0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
*
0000600

The volume header of your volume contains zeros only.

Without direct disk access I can guess the reasons only:

maybe the volume was "repaired to bits" by diskutil repairDisk disk0 or diskutil repairVolume disk0s1 (unlikely)
a wrong alternate volume header filled with zeros replaced the proper volume header
the partition map of the disk was manipulated accidentally (e.g. trying to delete the Debian partitions, you also deleted the macOS recovery partition or the macOS recovery partition and the CoreStorage container have been fused).

To further diagnose the disk it would require direct access (e.g. via TeamViewer) to check various invisible disk structures. It's too difficult and lengthy to answer all possible circumstances comprehensively without disk access.

Examples how lengthy solution processes are (these are no answers to your question):

As an alternative you can try to rsync the content of the volume to an external disk. With the proper options set the external volume should be bootable afterwards.

Links:

Related Solutions

I think I messed up the Fusion Drive on the 1TB iMac (with BootCamp)

Theoretically everything is fine with your Fusion Drive. Fusion Drives look like this. Disk0 is your SSD with 121 GB and disk1 is your HDD with ~1 TB (~1.121 TB summed up).

The larger parts of your SSD (disk0s2) and your HDD (disk1s2) are pooled to a CoreStorage LVG (Fusion Drive: disk3) with a size of 967.8 GB. The rest is reserved for EFIs, a Recovery HD (alltogether ~1.3 GB) and your old Windows partition - now probably free space (~152 GB).

The logical volume 'Macintosh HD' (967.8 GB) spans disk0s2 and disk1s2. This is the first 'Macintosh HD' in picture 1. The volume 'Macintosh HD' - it's the one visible on the desktop - should ideally also have about 967.8 GB. This is the second 'Macintosh HD' in picture 1.
In fact it has only 852.67 GB (see picture 3).

In the second picture the logical volume 'Macintosh HD' is the first listed in black, the volume 'Macintosh HD' is the second listed in black, the other two 'Macintosh HD's listed in grey are the parts of your SSD and HDD dedicated to the logical volume 'Macintosh HD'.

In my opinion something went wrong after deleting various partitions with the Bootcamp Assistant/Disk Utility or in Windows.

Preparation:

Detach any external drive (especially your external Time Machine backup drive)
Restart to Internet Recovery Mode by pressing alt cmd R at startup.
The prerequisites are the latest firmware update installed, either ethernet or WLAN (WPA/WPA2) and a router with DHCP activated.
On a 50 Mbps-line it takes about 4 min (presenting a small animated globe) to boot into a recovery netboot image which usually is loaded from an apple/akamai server.

I recommend ethernet because it's more reliable. If you are restricted to WIFI and the boot process fails, just restart your Mac until you succeed booting.

Alternatively you may start from a bootable installer thumb drive (preferably Mavericks or Yosemite) or a thumb drive containing a full system (preferably Mavericks or Yosemite).

Now you may either repair CoreStorage or rebuild your Fusion Drive:

'Repair CoreStorage' (not recommended):

First i would try to check the volume 'Macintosh HD' with Disk Utility. If the volume is corrupted consider a reinstall of Mac OS X.
If the volume is ok quit Disk Utility
Open Terminal and enter diskutil unmountDisk /dev/LVIdentifier and both diskutil unmountDisk /dev/DiskContainingApple_CoreStorageIdentifier
In your case: first diskutil unmountDisk /dev/disk3 then diskutil unmountDisk /dev/disk0 and diskutil unmountDisk /dev/disk1
remove the EFI NO NAME partition with gpt remove -i IndexNumberOfEFINoName DiskIdentifier:
gpt remove -i 4 disk1
Remount the CoreStorage disks and then the Logical Volume:
In your case: first diskutil mountDisk /dev/disk0 and diskutil mountDisk /dev/disk1 and then diskutil mount /dev/disk3.

enter gpt -r -vvv show /dev/diskIdentfierOfApple_CoreStorage to get infos of your HDD CoreStorage disk.
In your case: gpt -r -vvv show /dev/disk1
It should look like this:

-bash-3.2# gpt -r -vvv show /dev/disk1
gpt show: /dev/disk1: mediasize=1000204886016; sectorsize=512;         blocks=1953525168
gpt show: /dev/disk1: PMBR at sector 0
gpt show: /dev/disk1: Pri GPT at sector 1
gpt show: /dev/disk1: GPT partition: type=C12A7328-F81F-11D2-BA4B-00A0C93EC93B, start=40, size=409600
gpt show: /dev/disk1: GPT partition: type=53746F72-6167-11AA-AA11-00306543ECAC, start=409640, size=1671210848
gpt show: /dev/disk1: GPT partition: type=426F6F74-0000-11AA-AA11-00306543ECAC, start=1671620488, size=1269760
gpt show: /dev/disk1: Sec GPT at sector 1953525167                               
     start          size  index contents                                        
         0             1        PMBR                                            
         1             1        Pri GPT header                                  
         2            32        Pri GPT table                                   
        34             6
        40        409600      1 GPT part - C12A7328-F81F-11D2-BA4B-00A0C93EC93B
    409640    1671210848      2 GPT part - 53746F72-6167-11AA-AA11-00306543ECAC
1671620488       1269760      3 GPT part - 426F6F74-0000-11AA-AA11-00306543ECAC
1672890248     280634887
1953525135            32        Sec GPT table
1953525167             1        Sec GPT header

The free space on your HDD has 280634887 blocks. Please calculate the biggest block number dividable through 8. That's 280634880 blocks (á 512 bytes) which equals 143685058560 B or ~143.7 GB. Add the size of your HDD CoreStorage Physical Volume (852666400768 B) The result is 143685058560 B + 852666400768 B = 996351459328 B
Resize your HDD CoreStorage physical volume with diskutil cs resizeDisk HDDPVUUID newsize
In your case: diskutil cs resizeDisk 93892BE8-2B7F-4ABD-A4C3-984495DCD98D 996351459328b
Calculate the maximal size of your CoreStorage Logical Volume in diskutil cs list: (size disk0s2) + (size disk1s2) In your case that's 120988852224 B + 996351459328 B = 1117340311552 B. That should be the size of your refreshed Logical Volume Group.
Resize your Logical Volume with diskutil cs resizeVolume LVUUID LVGSize-128 MB In your case that's diskutil cs resizeVolume D237FFDC-7DA4-41D7-AC13-4CC7E5E8C0A0 1117212311552b. If you get an error (There is not enough free space...) choose a smaller size like 1117148311552b.
Quit Terminal and open Disk Utility.
Check your expanded CoreStorage Volume for errors.
Quit Disk Utility, choose your CS volume as startup disk and restart your Mac

'Rebuild Fusion Drive' (recommended if you have a Time Machine backup)

Booted to Internet Recovery Mode open Utilities → Terminal in the menubar and enter:
diskutil cs list to get the CoreStorage listing.
Copy the Logical Volume UUID, it's the fifth listed.
Now delete the Logical Volume with diskutil cs deleteVolume LVUUID.
In your case: diskutil cs deleteVolume D237FFDC-7DA4-41D7-AC13-4CC7E5E8C0A0.
Copy the Logical Volume Group UUID, it's the first listed in the listing of diskutil cs list.
Then delete the Logical Volume Group with diskutil cs delete LVGUUID.
In your case: diskutil cs delete 1EFE58BC-3613-44C4-86EE-D816F3B66E3E
Enter exit and quit 'Terminal'
Open 'Disk Utility'. Enter 'Ignore' if you are asked to fix the drives.
Choose your SSD and partition it: 1 Partition Mac OS X Extended (Journaled), hit the Options button and choose GUID Partiton table and hit OK and Apply.
Please check that the size is ~121 GB

Example:
Choose your HDD and partition it: 1 Partition Mac OS X Extended (Journaled), hit the Options button and choose GUID Partiton table and hit OK and Apply.
Please check that the size is ~1 TB

Example:
Quit Disk Utility and open Terminal
Enter diskutil list

Example (your disk identifiers and sizes are different of course: Your volume SSD probably has the Identifier disk0s2 and the size 121 GB and your volume HDD probably has the Identifier disk1s2 and the size 1.0 TB):
Enter diskutil cs create "Name" IdentifierSSD IdentifierHDD
In your case probably diskutil cs create "Macintosh HD" disk0s2 disk1s2.

Copy the resulting LVGUUID

Example:
Enter diskutil cs CreateVolume LVGUUID jhfs+ "Macintosh HD" 100%.

Example:
Enter diskutil cs list
Check the size of your Logical Volume. It should have the size ~1.121 TB

Example:
Quit Terminal
Open 'Disk Utility' and check your newly created volume for errors
Quit 'Disk Utility'
Attach your external Time Machine backup drive or check this answer if you use NAS or another network share.
Open 'Restore from Time Machine Backup'
Choose the appropriate Time Machine backup and restore your system
Reboot to your restored system.
Unmount and detach your Time Machine backup drive
Open 'Terminal' and enter 'diskutil list'
Check if your 'Recovery HD' is listed.
If your 'Recovery HD' is missing, usually reinstalling your current system with the latest available system installer (e.g. 'Install OS X Mavericks (10.9.5)' if Mavericks is currently installed) will recreate it without loosing any data. AFAIK Recovery Partition Creator 3.8 will NOT create a Recovery HD on CoreStorage volumes.
After reinstalling the system with the latest available system installer open App Store and install the latest security fixes.

How to rebuild Mac partition showing unexpected GPT table size

Based on the latest information posted in the question, here is what to enter. The assumption is the values posted are correct. The drive used a 4096 sector size. Since image files are fixed at a 512 byte sector size, all the values need to be multiplied by 8.

Note: You may get an error message when entering the command to destroy the GPT. You should ignore this message.

sudo chown $USER:staff path/to/file.dmg
hdiutil attach -nomount path/to/file.dmg
gpt destroy disk2
gpt create disk2
gpt add -i 1 -b $((6*8)) -s $(((51205-6+1)*8)) -t efi disk2
gpt add -i 2 -b $((51206*8)) -s $(((732533871-51206+1)*8)) -t hfs disk2
diskutil mount disk3

The GPT you posed has a partition type GUID for Core Storage, but the header you posted for this partition indicates the partition type GUID should be for a Hierarchical File System Plus (HFS+) partition. My answer assumed the header is correct.

References

The 16,384 byte size requirement for the GPT Partition Entry Array is defined in section 5.3.1 "GPT overview" on page 117 of the Unified Extensible Firmware Interface (UEFI) Specification version 2.8, March 2019.

Technical Note TN1150: HFS Plus Volume Format

GUID Partition Table

Best Answer

Related Solutions

I think I messed up the Fusion Drive on the 1TB iMac (with BootCamp)

How to rebuild Mac partition showing unexpected GPT table size

References

Related Question