3

How do I make a "sector level" copy of a 4TB external hard drive that contains Filevault 2-encrypted partitions? The hard drive has three partitions each encrypted using Filevault 2. I have all three of the filevault keys if it matters. I case I'm using the wrong term, by "sector level" I mean an exact copy of the drive bit for bit including deleted information.

For background - I am working to recover some photos. I want to recover a subfolder and files contained within using data recovery software. When I run a scan using disk recovery software on my external drive I'm told I get erroneous results because Filevault 2 is on. I had used the partition cloning feature contained within the data recovery software I am using but am told by the software company who makes it that it won't work accurately with Filevault drives/partitions. An independent data recovery professional told me I need to first make a sector level copy of the external drive, then decrypt that copy, then run the scan with the data recovery software to see correct results.

Thank you for your assistance!

P.S. Adding specific drive info. /dev/disk6/ is input disk (4 TB with the 3 FileVault 2 partitions) and /dev/disk3 is output disk (labelled 4-output which is a blank 4TB) (FYI: disk2, disk4, and disk5 are within the same JBOD now which I'll unmount other disks or physically pull when I do DD to be safe).

Mikes-MacBook-Pro-3:~ mikej$ diskutil list
/dev/disk0 (internal, physical):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *251.0 GB   disk0
   1:                        EFI EFI                     209.7 MB   disk0s1
   2:          Apple_CoreStorage Mike HD                 250.1 GB   disk0s2
   3:                 Apple_Boot Recovery HD             650.1 MB   disk0s3
/dev/disk1 (internal, virtual):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:                  Apple_HFS Mike HD                +249.8 GB   disk1
                                 Logical Volume on disk0s2
                                 6E587EBB-2506-41F2-85D2-8F6997BF22D6
                                 Unlocked Encrypted
/dev/disk2 (external, physical):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *4.0 TB     disk2
   1:                        EFI EFI                     209.7 MB   disk2s1
   2:                  Apple_HFS 2a-MirrorIncremental    4.0 TB     disk2s2
/dev/disk3 (external, physical):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *4.0 TB     disk3
   1:                        EFI EFI                     209.7 MB   disk3s1
   2:                  Apple_HFS 4-output                4.0 TB     disk3s2
/dev/disk4 (external, physical):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *4.0 TB     disk4
   1:                        EFI EFI                     209.7 MB   disk4s1
   2:                  Apple_HFS 1-MasterStorage         4.0 TB     disk4s2
/dev/disk5 (external, physical):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *4.0 TB     disk5
   1:                        EFI EFI                     209.7 MB   disk5s1
   2:                  Apple_HFS 3-scratch               4.0 TB     disk5s2
/dev/disk6 (external, physical):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *4.0 TB     disk6
   1:                        EFI EFI                     314.6 MB   disk6s1
   2:          Apple_CoreStorage Clone                   1.0 TB     disk6s2
   3:                 Apple_Boot Boot OS X               134.2 MB   disk6s3
   4:          Apple_CoreStorage MJTimeMachine           499.8 GB   disk6s4
   5:                 Apple_Boot Boot OS X               134.2 MB   disk6s5
   6:          Apple_CoreStorage Media                   2.5 TB     disk6s6
   7:                 Apple_Boot Boot OS X               134.2 MB   disk6s7
/dev/disk7 (external, virtual):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:                  Apple_HFS MJTimeMachine          +499.4 GB   disk7
                                 Logical Volume on disk6s4
                                 268E67C3-6199-4E50-99FA-E85322903D95
                                 Unlocked Encrypted
/dev/disk8 (external, virtual):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:                 Apple_HFSX CloneMikeHD            +1000.0 GB  disk8
                                 Logical Volume on disk6s2
                                 DAA42A81-D781-4B45-A516-0342CB137788
                                 Unlocked Encrypted
/dev/disk9 (external, virtual):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:                 Apple_HFSX Media                  +2.5 TB     disk9
                                 Logical Volume on disk6s6
                                 BE5B9EBC-6DCB-49C5-B055-B00C49864795
                                 Unlocked Encrypted
Mikes-MacBook-Pro-3:~ mikej$ sudo gpt -r show disk3
Password:
       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  7813365344      2  GPT part - 48465300-0000-11AA-AA11-00306543ECAC
  7813774984      262151         
  7814037135          32         Sec GPT table
  7814037167           1         Sec GPT header
Mikes-MacBook-Pro-3:~ mikej$ sudo gpt -r show disk6
      start       size  index  contents
          0          1         PMBR
          1          1         Pri GPT header
          2          4         Pri GPT table
          6      76800      1  GPT part - C12A7328-F81F-11D2-BA4B-00A0C93EC93B
      76806  244231258      2  GPT part - 53746F72-6167-11AA-AA11-00306543ECAC
  244308064      32768      3  GPT part - 426F6F74-0000-11AA-AA11-00306543ECAC
  244340832  122021070      4  GPT part - 53746F72-6167-11AA-AA11-00306543ECAC
  366361902      32768      5  GPT part - 426F6F74-0000-11AA-AA11-00306543ECAC
  366394670  610318797      6  GPT part - 53746F72-6167-11AA-AA11-00306543ECAC
  976713467      32768      7  GPT part - 426F6F74-0000-11AA-AA11-00306543ECAC
  976746235          4         Sec GPT table
  976746239          1         Sec GPT header
  • 1
    You can use dd in Terminal. It's free and comes with the OS. – user3439894 Aug 18 '16 at 19:24
  • @MikeJ which of the FileVault volumes contain the deleted pictures to recover? – klanomath Aug 19 '16 at 20:57
  • Media, at 2.5TB is where I'd expect them to be. – Mike J Aug 19 '16 at 21:06
  • @MikeJ I'm just writing an addendum to my answer! The disk identifiers will probably change after removing the JBOD. I will use disk3 as target and disk6 as source identifiers though. You have to adapt this later to the real identifiers. – klanomath Aug 19 '16 at 21:09
5

At least Carbon Copy Cloner is just a wrapper for either dd or rsync. I suspect that it's the same with SuperDuper!.

Since both tools (of which rsync is not needed here) are already included in OS X you don't have to buy it.

To clone one drive to another you have to prepare the source and the target drive.

Most sizes and commands containing sizes, disk identifiers or paths etc. below are just examples. You have to replace them by respective values found in your set up/listings.

  • Mark the source drive with a red sticker, if the source and target drive have identical cases!
  • Attach both drive but don't mount the encrypted FileVault volume. If it is already mounted unmount it. Detach all other external drives.
  • Open Terminal and enter diskutil list to get an overview. You will get a list of all attached drives similar to this one - your output may slightly differ):

    /dev/disk0
       #:                       TYPE NAME                    SIZE       IDENTIFIER
       0:      GUID_partition_scheme                        *121.3 GB   disk0
       1:                        EFI EFI                     209.7 MB   disk0s1
       2:          Apple_CoreStorage                         121.0 GB   disk0s2
       3:                 Apple_Boot Boot OS X               134.2 MB   disk0s3
    /dev/disk1
       #:                       TYPE NAME                    SIZE       IDENTIFIER
       0:      GUID_partition_scheme                        *3.0 TB     disk1
       1:                        EFI EFI                     209.7 MB   disk1s1
       2:          Apple_CoreStorage                         3.0 TB     disk1s2
       3:                 Apple_Boot Recovery HD             650.0 MB   disk1s3
    /dev/disk2
       #:                       TYPE NAME                    SIZE       IDENTIFIER
       0:                  Apple_HFS Macintosh HD           *3.1 TB     disk2
    /dev/disk3
       #:                       TYPE NAME                    SIZE       IDENTIFIER
       0:      GUID_partition_scheme                        *4.0 TB     disk3
       1:                        EFI EFI                     314.6 MB   disk3s1
       2:          Apple_CoreStorage Encrypted               4.0 TB     disk3s2
       3:                 Apple_Boot Boot OS X               134.2 MB   disk3s3
    /dev/disk4
       #:                       TYPE NAME                    SIZE       IDENTIFIER
       0:      GUID_partition_scheme                        *4.0 TB     disk4
       1:                        EFI EFI                     314.6 MB   disk4s1
       2:                  Apple_HFS Data                    4.0 TB     disk4s2
    

    Now you have to analyze the output. Here disk0 and disk1 are a 3.1 TB Fusion drive with the CoreStorage volume mounted as disk2. Disk3 is obviously the encrypted disk with deleted data which should be cloned. Disk4 is a spare drive and the target of the clone task. Disk4 has to have at least the same size as disk3! Check this with diskutil info disk3 and diskutil info disk4.

    Below I assume disk3 is the source and disk4 is the target of the clone task. Your disk identifiers may be different (e.g. disk2 and disk3)

  • Check the device block sizes with

    diskutil info disk3 | grep "Device Block Size:"
    diskutil info disk4 | grep "Device Block Size:"
    

    Usually the Device Block Size of ≥4 TB drives is 4096 Bytes. If the block sizes of disk3 and 4 are equal you are fine.

  • Now get the partition tables of the external drives with sudo gpt -r show diskX. The output should be similar to the one below:

    sudo gpt -r show disk3
          start       size  index  contents
              0          1         PMBR
              1          1         Pri GPT header
              2          4         Pri GPT table
              6      76800      1  GPT part - C12A7328-F81F-11D2-BA4B-00A0C93EC93B
          76806  976636661      2  GPT part - 53746F72-6167-11AA-AA11-00306543ECAC
      976713467      32768      3  GPT part - 426F6F74-0000-11AA-AA11-00306543ECAC
      976746235          4         Sec GPT table
      976746239          1         Sec GPT header
    sudo gpt -r show disk4
          start       size  index  contents
              0          1         PMBR
              1          1         Pri GPT header
              2          4         Pri GPT table
              6      76800      1  GPT part - C12A7328-F81F-11D2-BA4B-00A0C93EC93B
          76806  976636711      2  GPT part - 48465300-0000-11AA-AA11-00306543ECAC
      976713517      32768         
      976746285          4         Sec GPT table
      976746289          1         Sec GPT header
    

    Start and size values are block numbers or blocks. Block numbering starts at block 0! In my example disk4 is slightly bigger (50 blocks) than disk3.

  • First you have to create identical "mirror" partition entries on disk4 (with the same values as those on disk3).

  • Unmount the target drive:

    diskutil umountDisk disk4
    
  • Destroy and recreate the GUID partition table (and/or remove an MBR partition table) of the target drive:

    sudo gpt destroy disk4
    sudo gpt create -f disk4
    
  • get an overview of disk4 with sudo gpt -r show disk4. It should look like this:

          start       size  index  contents
              0          1         PMBR
              1          1         Pri GPT header
              2          4         Pri GPT table
              6  976746279
      976746285          4         Sec GPT table
      976746289          1         Sec GPT header
    
  • Now recreate the first two partitions of disk 3 with the values of disk3 on disk4:

    sudo gpt add -i 1 -b 6 -s 76800 -t C12A7328-F81F-11D2-BA4B-00A0C93EC93B disk4
    sudo gpt add -i 2 -b 76806 -s 976636661 -t 53746F72-6167-11AA-AA11-00306543ECAC disk4
    

    This will only modify the GUID partition table (the first 6 and the last 5 blocks) of disk4.

  • Recheck the partition table of disk4 with sudo gpt -r show disk4. It should look like this now:

          start       size  index  contents
              0          1         PMBR
              1          1         Pri GPT header
              2          4         Pri GPT table
              6      76800      1  GPT part - C12A7328-F81F-11D2-BA4B-00A0C93EC93B
          76806  976636661      2  GPT part - 53746F72-6167-11AA-AA11-00306543ECAC
      976713467      32818         
      976746285          4         Sec GPT table
      976746289          1         Sec GPT header
    
  • Now clone the content of disk3s1 and disk3s2 to disk4s1 and disk4s2:

    sudo dd if=/dev/disk3s1 of=/dev/disk4s1 bs=1m
    sudo dd if=/dev/disk3s2 of=/dev/disk4s2 bs=1m
    

    Clone disk3s3 to a file:

    sudo dd if=/dev/disk3s3 of=/Users/user_name/Desktop/bootosx.cdr bs=1m
    

    Replace user_name by your short user name.

    Cloning the first partition (300 MiB) is fast (~3.5 seconds). Cloning the second partition (4 TB) will take about 11 hours (USB3/Thunderbolt) or 30-50 hours (USB2).

  • Unmount the source drive:

    diskutil umountDisk disk3
    

    and detach it. Check if the target drive still is disk4: diskutil list.

  • add the third partition on disk4:

    sudo gpt add -i 3 -b 976713467 -s 32768 -t 426F6F74-0000-11AA-AA11-00306543ECAC disk4
    
  • Clone bootosx.cdr to disk4s3:

    sudo dd if=/Users/user_name/Desktop/bootosx.cdr of=/dev/disk4s3 bs=1m
    
  • After the cloning to the last partition on the target disk is done, you should be asked for the FileVault password.

  • Don't attach the source and the target drive at the same time on one Mac. They have identical UUIDS for the LVG/PV/LVF/LV (the CoreStorage Volume Group containing the FileVault container) and I don't know if and how they "coexist".


Adaption to the actual set up of the OP

The target disk (disk3) has a different Device Block Size (512 Byte). The source disk has several FileFault2 volumes.

Under these circumstances some partition table values of the target disk (disk3) have to be adjusted and only one of the CoreStorage partitions has to be cloned with dd.

  • Unmount the target drive:

    diskutil umountDisk disk3
    
  • Destroy and recreate the GUID partition table (and/or remove an MBR partition table) of the target drive:

    sudo gpt destroy disk3
    sudo gpt create -f disk3
    
  • get an overview of disk3 with sudo gpt -r show disk3. It should look like this:

           start        size  index  contents
               0           1         PMBR
               1           1         Pri GPT header
               2          32         Pri GPT table
              34  7814037101         
      7814037135          32         Sec GPT table
      7814037167           1         Sec GPT header
    
  • Now recreate the first and the sixth partition of disk 6 with modified values on disk3. Since the Device Block Sizes of the two disks are different you have to recalculate start blocks and sizes (usually by multiplying with 8):

    sudo gpt add -i 1 -b 40 -s 614400 -t C12A7328-F81F-11D2-BA4B-00A0C93EC93B disk3
    sudo gpt add -i 2 -b 614440 -s 4882550376 -t 53746F72-6167-11AA-AA11-00306543ECAC disk3
    

    This will only modify the GUID partition table of disk3.

  • Recheck the partition table of disk3 with sudo gpt -r show disk3. It should look like this now:

           start        size  index  contents
               0           1         PMBR
               1           1         Pri GPT header
               2          32         Pri GPT table
              34          40
              40      614400      1  GPT part - C12A7328-F81F-11D2-BA4B-00A0C93EC93B
          614440  4882550376      2  GPT part - 53746F72-6167-11AA-AA11-00306543ECAC         
      4883164816  2930872319
      7814037135          32         Sec GPT table
      7814037167           1         Sec GPT header
    
  • Now clone the content of disk6s1 and disk6s6 to disk3s1 and disk3s2:

    sudo dd if=/dev/disk6s1 of=/dev/disk3s1 bs=1m
    sudo dd if=/dev/disk6s6 of=/dev/disk3s2 bs=1m
    

    Clone disk6s7 to a file:

    sudo dd if=/dev/disk6s7 of=/Users/user_name/Desktop/bootosx.cdr bs=1m
    

    Replace user_name by your short user name.

    Cloning the first partition (300 MiB) is fast (~3.5 seconds). Cloning the FileVault partition (2.5 TB) will take about 7 hours (USB3/Thunderbolt) or 20-35 hours (USB2).

  • Unmount the source drive:

    diskutil umountDisk disk6
    

    and detach it. Check if the target drive still is disk3: diskutil list.

  • add the third partition on disk3:

    sudo gpt add -i 3 -b 4883164816 -s 262144 -t 426F6F74-0000-11AA-AA11-00306543ECAC disk3
    
  • Clone bootosx.cdr to disk3s3:

    sudo dd if=/Users/user_name/Desktop/bootosx.cdr of=/dev/disk3s3 bs=1m
    
  • After the cloning to the last partition on the target disk is done, you should be asked for the FileVault password.
  • If you don't get a password prompt, you can mount it by entering diskutil cs list and diskutil cs unlockVolume LVUUID (with LVUUID: UUID of the encrypted CoreStorage volume - in your case probably BE5B9EBC-6DCB-49C5-B055-B00C49864795)

Please add a comment (with @klanomath) if you don't get a password prompt or run into problems.

  • Wow. Whoa. @klanbmath - I'm impressed and a bit daunted. It looks straightforward if I just go step by step though. I'd take you up on your offer to modify your text based on my output but it doesn't seem like I can fit everything in the comment field. I'll update my original post in a bit once I figure out formatting. – Mike J Aug 19 '16 at 17:50
  • @klanbmath Device block sizes appear different: Mikes-MacBook-Pro-3:~ mikej$ diskutil info disk3 | grep "Device Block Size:" Device Block Size: 512 Bytes Mikes-MacBook-Pro-3:~ mikej$ diskutil info disk6 | grep "Device Block Size:" Device Block Size: 4096 Bytes – Mike J Aug 19 '16 at 21:27
  • @MikeJ I considered this in my addenedum – klanomath Aug 19 '16 at 21:49
  • Thanks again for your helpful work. I'll give this a try in a few days and report back. – Mike J Aug 20 '16 at 0:10
  • Hi @klanomath - With the exception of the last point you made saying I'd be asked for the FileVault password, everything worked. Even though I wasn't asked for the FileVault password, I could still see all the folders and files on the cloned version. I then did a right click, decrypt and it completed without errors. However I'm falling short on my original objective and that was to see if data recovery would be different. Do you know if I just DD the whole original disk to get a copy of all 3 partitions, then decrypt? – Mike J Aug 25 '16 at 19:20
1

I suggest using Carbon Copy Cloner, as I have for years. It can duplicate any volume, even if it is a bootable HDD and FileVault 2 protected, however it costs around $50. There is also Shirt Pocket's SuperDuper, that costs $39.55.

  • Thanks, however I think both just do file level copy. – Mike J Aug 18 '16 at 22:42

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