Creating Bootable Clone from Apple Silicon Mac

[mschmitt]

I got past the authorize/owner loop. I did two things differently:

• Restarted the computer after the clone, before trying to set the Startup disk
• Waited longer before trying to set the Startup disk

I think the first time I tried this (which didn't get the authentication loop), I started the clone before going to bed. But the more recent attempts, I did the clone and immediately tried to start from it. I noticed that when I did that, Spotlight was still furiously indexing the volume; perhaps that interfered.

This time it didn't ask me to set an owner, only to authorize a user account.

The restart crashed (dyld cache), so I used macOS Recovery to reinstall Ventura on the backup drive. And it worked! It booted from the backup SSD (Ventura 13.6.2, same as on internal drive), and I could start FileVault encryption -- when I got that far once before with the HD backup, FileVault gave an error.

This does make me wonder: if the authentication/owners loop was due to either needing to reboot or wait for Spotlight, what would have happened when I did the SuperDuper! Smart Update on top of the clean macOS install, if I had rebooted and waited? Same error or something else?

Anyway, next milestone will be if it survives a Smart Update. I'd think it will.

[dnanian]

I can't see how Spotlight could interfere with this. Quite strange.

[greengrass]

Originally Posted by mschmitt

I'm hitting two main issues right now:

• First time I tried it, it crashed on the restart, because asr didn't rebuild the dyld cache. We've seen this before.
• Now I can't even get that far. It won't let me complete the authorize users/set owner process.

When you did it, did you try to restart by selecting in the System Settings? Or did you just reboot and hold the power button to choose a different drive?

Did it ask you to authorize a user and select an owner?

I did the reboot by holding the power button while choosing to restart. I don't remember it asking to authorize a user. There is only one user on this machine.

[gbdoc]

This may not resolve everyone’s problems, but it’s important to know that for clones to be bootable on silicon Macs (I have an M2 MBAir/Sonoma) you absolutely need to have a very fast external drive. IME, HDD won’t do the job, you need an SSD. I got an OWC envoy express thunderbolt 3 (usb-c) and fitted it out with a 1 TB OWC Aura P12 Pro. Now my SD! clones are bootable with no hassle. I did the same for a friend with the same machine. I’m not too tech-savvy, so I don’t know whether there might be other drives fast enough, but thunderbolt 3 surely is. I would suggest, Dave, that you make this very clear in your instructions.

[dnanian]

In general, I suggest USB-C/3 or later SSDs, yes. Slower drives *can* work, though...and remember, a drive does not have to be bootable to be restorable...

[gbdoc]

Just a pleasing update:

Just updated to Sonoma 14.3, cloned it to my external SSD, and it*s still bootable, problem-free.

[Gusto5]

Originally Posted by dnanian

...remember, a drive does not have to be bootable to be restorable...

Could you expand on your statement quoted above?
I have always assumed if I can't boot up from a backup then I can't re-install the backup over an existing internal boot drive that has become perhaps corrupted. Having a bootable clone makes the process so fast and generally trouble free. If I backup my M3 MBP14 to an HDD, and it isn't bootable how do I restore my MBP from the non bootable HDD?

[dnanian]

The OS cannot be copied into an Apple silicon Mac - only out. It always has to be either installed (from Recovery) or a recovery image needs to be installed by Configurator (which may become easier someday with firmware support).

As such, all full restores on Apple silicon are done by clean installing the OS, then -- when prompted -- selecting the backup to restore. That backup can either be a "full" bootable copy with an OS, or it can be a "Backup - all files" with "Smart Update" - basically, a full copy of the Data volume, without an OS (since the OS doesn't get restored anyway).

[Gusto5]

Originally Posted by dnanian

In general, I suggest USB-C/3 or later SSDs, yes. Slower drives *can* work,.

From the first part of your previous answer, quoted above, you appear to recommend using a SSD over a HDD as the backup hard drive for an Apple silicon Mac. If using a SSD or a HDD result in the same non bootable backup why do you suggest a SSD is a better choice for a backup hard drive, beyond file copy speed/time?

[dnanian]

General reliability along with speed, and you're more likely to have a bootable copy on SSD.