As directed by an answer on: How to create an accurate byte-level copy of an SSD to another drive?, I tried to clone my Mac internal disk of 256GB. When I ran diskutil I got this:

/dev/disk0 (internal):
║ GUID_partition_scheme ║                 ║ 251.0 GB ║ disk0   ║  ║
║ EFI                   ║ EFI             ║ 314.6 MB ║ disk0s1 ║  ║
║ Apple_APFS            ║ Container disk2 ║ 250.7 GB ║ disk0s2 ║  ║

/dev/disk2 (synthesised):
║ APFS Container Scheme ║ -                      ║ +250.7 GB ║ disk2   ║
║                       ║ Physical Store disk0s2 ║           ║         ║
║ APFS Volume           ║ Macintosh HD           ║ 234.1 GB  ║ disk2s1 ║
║ APFS Volume           ║ Preboot                ║ 21.4 MB   ║ disk2s2 ║
║ APFS Volume           ║ Recovery               ║ 524.7 MB  ║ disk2s3 ║
║ APFS Volume           ║ VM                     ║ 1.1 GB    ║ disk2s4 ║

I understand from the output that while the actual disk is disk0, the partition disk0s2 is mounted as separate disk disk2. I decided to just clone disk0 directly with

dd if=/dev/rdisk0 of=/my/chosen/path bs=1m

May I ask if it would make any difference if I had cloned partitions separately. So instead of the above, would

dd if=/dev/rdisk0s1 of=/my/chosen/path bs=1m; 
dd if=/dev/rdisk0s2 of=/my/chosen/path bs=1m;


dd if=/dev/rdisk0s1 of=/my/chosen/path bs=1m; 
dd if=/dev/rdisk2s1 of=/my/chosen/path bs=1m;
dd if=/dev/rdisk2s2 of=/my/chosen/path bs=1m;
dd if=/dev/rdisk2s3 of=/my/chosen/path bs=1m;
dd if=/dev/rdisk2s4 of=/my/chosen/path bs=1m;

make any difference?

If context is needed to decide whether there’s a difference or not, please consider the same context as in How to create an accurate byte-level copy of an SSD to another drive? - that it is intended that data recovery for lost files is to be done on the clone in the future.

1 Answer 1


Partitions are fixed in size, so taking images of each partition individually does the same thing as taking an image of the whole disk. The only small difference is that any gaps between partitions (if they exist) are only included in the full disk image. But this gaps are „invisible“ anyway, so for any user-level data duplication and recovery operations this doesn’t make a difference.

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