Messed up 1TB Fusion Drive Partitions (on iMac 5K) - 100% Disk Space used

Question

my I'Mac 5k won't boot.

What happened:

I did some image editing in photoshop and instead I resized the image to 1100px i typed 11000px. After this mistake i got the rainbow circle of death. I tried to restart my mac but after several tries nothing happened. (loading bar and then the mac shutdown again and again)

What I tried:

• I did some research and restarted to Recovery Mode CMD + R. (Also in Internet Mode CMD + R + Alt
• Then I loaded up the Disk Utility and saw something strange.
• The Disk Space is now 100% used!
• Macintosh HD is greyed out
• I also tried to mount the Partition to remove some data, but I failed.

diskutil cs list

-bash-3.2# diskutil cs list
CoreStorage logical volume groups (1 found)
|
+-- Logical Volume Group B16B79BA-68A0-479E-B05B-449885182660
    =========================================================
    Name:         Macintosh HD
    Status:       Online
    Size:         1120333979648 B (1.1 TB)
    Free Space:   4763394048 B (4.8 GB)
    |
    +- Logical Volume Family F0016DF7-BD2B-40D3-AE3E-D0A412F61A6D
        ----------------------------------------------------------
        Encryption Status:       Unlocked
        Encryption Type:         None
        Conversion Status:       NoConversion
        Conversion Direction:    -none-
        Has Encrypted Extents:   No
        Fully Secure:            No
        Passphrase Required:     No
        |
        +-> Logical Volume 0844B760-CD5F-4913-95F5-826A8455A59B
            ---------------------------------------------------
            Disk:                  disk3
            Status:                Online
            Size (Total):          1114835517440 B (1.1 TB)
            Conversion Progress:   -none-
            Revertible:            No
            LV Name:               Macintosh HD
            Volume Name:           Macintosh HD
            Content Hint:          Apple_HFS
-bash-3.2# 

diskutil list

-bash-3.2# diskutil list
/dev/disk0
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *1.0 TB     disk0
   1:                        EFI EFI                     209.7 MB   disk0s1
   2:          Apple_CoreStorage                         999.3 GB   disk0s2
   3:                 Apple_Boot Recovery HD             650.0 MB   disk0s3
/dev/disk1
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *121.3 GB   disk1
   1:                        EFI EFI                     209.7 MB   disk1s1
   2:          Apple_CoreStorage                         121.0 GB   disk1s2
   3:                 Apple_Boot Boot OS X               134.2 MB   disk1s3
/dev/disk2
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:     Apple_partition_scheme                        *1.3 GB     disk2
   1:        Apple_partition_map                         30.7 KB    disk2s1
   2:                  Apple_HFS OS X Base System        1.3 GB     disk2s2
/dev/disk3
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:                  Apple_HFS Macintosh HD           *1.1 TB     disk3
                                 Logical Volume on disk1s2, disk0s2
                                 0844B760-CD5F-4913-95F5-826A8455A59B
                                 Unencrypted
/dev/disk4
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:                            untitled               *5.2 MB     disk4
/dev/disk5
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:                            untitled               *524.3 KB   disk5
/dev/disk6
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:                            untitled               *524.3 KB   disk6
/dev/disk7
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:                            untitled               *524.3 KB   disk7
/dev/disk8
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:                            untitled               *524.3 KB   disk8
/dev/disk9
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:                            untitled               *524.3 KB   disk9
/dev/disk10
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:                            untitled               *6.3 MB     disk10
/dev/disk11
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:                            untitled               *2.1 MB     disk11
/dev/disk12
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:                            untitled               *1.0 MB     disk12
/dev/disk13
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:                            untitled               *524.3 KB   disk13
/dev/disk14
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:                            untitled               *524.3 KB   disk14
/dev/disk15
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:                            untitled               *1.0 MB     disk15
/dev/disk16
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:                            untitled               *6.3 MB     disk16
/dev/disk17
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:     FDisk_partition_scheme                        *8.1 GB     disk17
   1:                 DOS_FAT_32 USB DISK                8.1 GB     disk17s1
-bash-3.2# 

I also looked at similiar threads. But I'm not sure if they are comparable to my problems. They all about Bootcamp and boot loaders. - Sorry if I ask twice:

Fusion Drive seems to be messed up

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

I don't have any Timemachine Backup and If its possible I would also reinstall everything but I need some crucial data of the HDD.

EDIT: Added another Screenshot from Recovery Mode. Where you can see 1,11TB used for "Other". I had ~900GB free of disk space before this issue.

EDIT1: I can succesfully boot so single user mode cmd + S. I did

fsck -fy

and I got: “The volume (name) appears to be OK”. I could also see my whole file structure. Last I rebooted but same behaviour - so no luck here

EDIT2:
Output of gpt -r show /dev/disk0 and gpt -r show /dev/disk1

EDIT3:

output of df:

Filesystem  512-blocks        Used  Available Capacity   iused     ifree %iused  Mounted on
/dev/disk2  2177413120   388991584 1787909536    18%  48687946 223488692  18%   /

BTW: The number of Used blocks + Available blocks + 512,000 blocks = number of 512-blocks. So 512,000 blocks are probably used for some CoreStorage administrative tasks.

Answer 1

I would try the following since all basic configs/lists/outputs look fine:

• boot to Single User Mode
• /sbin/fsck -fy

• Display free disk space /bin/df

  Example:

  Filesystem  512-blocks        Used  Available Capacity   iused     ifree %iused  Mounted on
  /dev/disk2  6066780416  5644868776  421399640    94% 705672595  52674955   93%   /
  

  Here 94% of the disk space and 93% of the inodes are used.

• If free disk space ~0 /sbin/mount -uw /

• Change directory cd /Users/user_name/path/to/big/file and list files with ls
• Print working directory to be sure pwd
• rm big_file
• Display free disk space again /bin/df
• boot to main volume with exit

You may have to remove some really small files (size < 100 kb) first before you succeed deleting the big file.

---

If this fails get an external disk, partition and format it (JHFS+) it in Recovery Mode or with a second Mac. Attach it to the broken Mac, boot to single user mode (cmdS while booting), mount the external drive and rsync your user folder and other important files & folders to the external volume. Then erase Macintosh HD and reinstall OS X. You may also rsync your complete system!

Mounting an external drive to /Volumes (even though the boot drive is readable only) should be possible by using:

gpt -r show disk0/1/2 #search for the proper drive because *diskutil* won't work in SU mode
/sbin/mount_hfs -o nosuid -w /dev/disk2s2 /Volumes/ #mount the external drive (e.g. disk2s2) to /Volumes
rsync -aAvX /Users/user_name/ /Volumes/user_name #Backing up the user folder. 

If the above rsync options don't work use something like rsync -aE ... instead.

The root of the external drive is directly in /Volumes (so no volume name in-between like on a normal system: /Volumes/Volume_name_ext_drive/).

After rsync'ing check the content of the "new" user folder.

(Tested in a VM)