Cloning drive under macOS Big Sur

I used SuperDuper for almost 10 years.
Under Big Sur it no longer works reliable for me.

Anyone knows about a reliable way to clone a Mac to a new drive?

I’m not where I am able to link, but Dave has a post.

Net, you need a down level version of SD (which is linked)
and then clone your DATA “volume”. It is then possible to
install Big Sur onto that clone, to be able to boot

Here are the details:

It’s the January 31 Post


It’s actually easy. To accomplish this, use an old version of SuperDuper—specifically, v3.2.5—to copy the Data volume, which is shown in the older version!

v3.2.5 is well tested, having been on the market for quite some time, and is reliable. So we don’t have to worry about doing a broad beta test of a partially complete new release. It’s already tested, and I’ve been busy doing the additional testing necessary to prove it works on Big Sur.

Again, this will make a copy of the data that you need to preserve your stuff, both Applications and Data, while leaving the Sealed System Volume alone.

And it’s a valid source for “restore” during a clean install or migration! So restoration is easy and fast should it become necessary.


Yeah, I wish I had thought of this earlier.

So, if you’re on Big Sur, and you want to copy a startup drive, here’s what to do:

  1. Make sure you have your license information handy. You can retrieve it from SuperDuper’s Register… page should you need to.
  2. Download and install SuperDuper! v3.2.5 from here.
  3. Remove SuperDuper! from the “Full Disk Access” list in the Security & Privacy preference pane and restart your Mac. This is important, and works around an Apple bug triggered by the change of SuperDuper!'s bundle ID.
  4. Run SuperDuper and follow the steps to allow it Full Disk Access.
  5. If your license is missing, re-enter it from your license email.
  6. Turn off “Check for Updates” in our Preferences so we don’t nag you about v3.3.1.
  7. Select the “Data” volume in the source pop-up, and a new APFS backup volume in the destination pop-up, along with “Backup - all files” (or whatever script you want). If you already have a backup volume, you can use Disk Utility to select and delete just the backup System volume, rather than create a new one. After doing this, rename the Data volume to something sensible (remove “- Data”). Note that you may need to repair it with Disk First Aid before it will show up in SuperDuper.
  8. Make your copy as normal, set up your schedule as needed, etc. Your regular Smart Updates will work as expected.

To fully restore, it’s easiest to boot to recovery, erase the internal drive you want to restore to, reinstall the OS from Recovery mode, and then, when prompted to restore during the first boot of the fresh copy of macOS, point at the backup. All your data and applications will be brought in automatically.

If you want to make the backup bootable and have an Intel Mac, boot to Recovery (Cmd+R during power on) and install Big Sur to the backup drive. You can then start up from the backup. Note, though, that once made bootable, you can no longer copy to the backup until you delete the system volume as above. So don’tdo this unless you need to.


There’s a beta of superduper! that works with Big Sur now. Check the Shirt Pocket blog. I’m using it now for my iMac 5k and it seems to be working as advertised.

I tried it twice and it doesn’t show the data like it used to.
Not feeling comfortable the way it works now.

I too used SuperDuper for a very long time. After waiting for months for an update for Big Sur, I gave up and bought Carbon Copy Cloner.
I couldn’t be happier. Great app, great developer and it works reliably.
Very happy with CCC!


I used to use SD, but had issues and switched to Carbon Copy Cloner years ago. It works very well and Mike is always willing to help with questions…

1 Like

I resorted in docking the SSD in a “toaster” and reboot the Mac in recovery mode.
Formatted the drive and stated the installation of Big Sur on the external drive. Upon completion I started Migration assistant.
Once this is completed I will open the Mac (mini) and swab the worn out HD for the SSD.