Is it possible to copy a running Macbook's state (running Sierra) over to a new Macbook?

I can't use target disk mode for two reasons: one, I don't have a Firewire cable and am not sure where to get one on my tiny island; two, the old Macbook is broken: when restarted, it usually won't boot, and I fear it won't boot even into target disk mode. (At the moment, I'm keeping it running until the replacement arrives. Day five so far.)

There is a Time Machine backup, but I'm excluding a lot of non-essential files from it. If I added all those files just to transfer everything over, it'd enlarge the overall backup size forever, which I'd like to avoid.

  • Migration Assistant can help you transfer all the important stuff: support.apple.com/en-us/HT204350
    – owlswipe
    Commented Feb 12, 2017 at 23:11
  • 2
    And a Time Machine backup will do the job too. It won't "enlarge the overall backup size forever" (just temporarily) as you can delete all of the backup easily once you're done (through Finder).
    – owlswipe
    Commented Feb 12, 2017 at 23:12
  • I think Lanzarote Apple Repair has a Firewire cable but some fancy Firewire2TB or Firewire2USBC3 would be required because the new Macs don't have a Firewire interface!
    – klanomath
    Commented Feb 12, 2017 at 23:49
  • @klanomath ha, somehow that didn't come up in my search! Thanks!
    – Pekka
    Commented Feb 13, 2017 at 8:32

4 Answers 4


You can't clone a fully booted Mac to another completely booted Mac

Not completely accurate.

A fully booted mac can be copied, in it's entirely, to somewhere else. Use Carbon Copy Cloner (easy) or rsync (Unix guru).

The only place "somewhere else" cannot be is a booted volume. The hardware hosting the destination can be booted to the desktop, you just need a second partition on the drive and send the clone there.

You can also clone to an external drive or a disk image. In your case I would clone the old machine to the external drive that has Time Machine on it (NOT as a disk image), boot the new machine from the external, and clone again. Use Carbon Copy and it will not bother copying files that are already there.

You can do the clone-to-external part right now.


You can't clone a fully booted Mac to another completely booted Mac. At least some files and folders won't be overwritten because they are in use (e.g. the Mach kernel file).

Without some direct connection (e.g. Thunderbolt cable, Firewire-to-Thunderbolt cable, Firewire-to-USB 3C etc.) you are left with either the Migration Assistant or a Time Machine backup.

Your best bet is to make a complete Time Machine backup, boot the new Mac in Recovery Mode, attach the backup drive and restore the content of your old Mac.

Using the Migration Assistant and a network connection is probably rather slow because it will rely on Wi-Fi (assuming that the Wi-Fi chip in the old Mac is not as performant as the one in the new Mac).


I haven't tried - but I'd start with Carbon Copy Cloner - http://www.bombich.com or this, which I just discovered today: https://macdaddy.io/duplicate/


This is exactly what the free Duplicate is designed for. It adds a copy/paste contextual menu item to the Finder (using Finder Extensions, sanctioned by Apple) which allows anything to be copied and pasted to make a faithful duplicate - even a bootable disk.

Full disclosure: I am the author.

  • That looks awesome. When copying entire volumes, is it respectful of files that already exist and are identical to the ones in the source, potentially making it a "hot backup" solution as well?
    – Pekka
    Commented Mar 15, 2017 at 8:11
  • 1
    It doesn't overwrite existing files on the destination with files from the source, no matter what (even if they're older, etc). So it's a non-destructive full copy.
    – scanf
    Commented Mar 17, 2017 at 12:18

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .