SuperDuper cloned SSD won't boot?

Sorry Tom, it's only partially true. I must have misread when ploughing through reams of bumf.

They are not bootable if the internal SSD is damaged.

I can remember back in 2005 there was a top contributor to the Final Cut Express forum (who was always slagging off his employer!) who had a MacBook with a broken hard drive and kept it going for ages with a bootable plug in drive. He couldn't do that now with Silicon.

Here's the quote:-

In the past, a "bootable backup" was an indispensable troubleshooting device that even novice users could rely upon in case their production startup disk failed. The reliability of Apple's External Boot solution has waned in the past several years, however, and the situation has grown starkly worse on the new Apple Silicon platform. Apple Silicon Macs will not start up (at all) if the internal storage is damaged or otherwise incapacitated, so there is very little value, if any, to maintaining a bootable rescue device for those Macs.

It has also grown increasingly difficult to make a copy of the operating system. Starting in macOS Big Sur (11.0), the system resides on a cryptographically sealed "Signed System Volume" that can only be copied by an Apple-proprietary utility. That utility is very one-dimensional; choosing to copy the system requires that we sacrifice other backup features, e.g. we cannot copy the system and retain versioned backups of your data. Due to these changes and the limitations of Apple's new "Apple Silicon" platform, creating an external bootable device is not only less approachable for novice users, it's also less likely to serve as a reliable troubleshooting device.

I have not seen that but their latest claims are that it is bootable . . . that's one of their key selling points.

I have just realised that my T5 was connected via a USB 3.0 hub and am wondering whether that could be the cause of the failure.

So I am going to plug it directly into the back of the iMac and try booting again.

If that fails I will erase and make a new bootable backup with the T5 plugged in directly and if that fails I will start praying.

It's a shame because for the last decade and more various members of the FCP forum have recommended both these apps and when I finally get round to using one, I can't get it to work. 😤

From other information I have gleaned it would appear that creating a bootable volume directly from SuperDuper or CCC is problematic if not impossible.

As a workaround I could use my CRUCIAL SSD to boot into Catalina and then copy the data from my Samsung SSD.

The day started so optimistically and then degenerated but I suppose I still have a backup.

Long story . . . short.

I downloaded Carbon Copy Cloner, erased my Samsung T5 with Disk Utility and set up CCC in Legacy Mode to clone the OS as well as the data.

It took 35 minutes to do its thing and I appeared to have a bootable cloned drive.

So I restarted the computer after selecting the T5 and everything went well for about 30 seconds whereupon the progress bar froze and 5 minutes later I got the immortal message saying that my Mac had restarted because of a problem.

Exactly the same as SuperDuper!

So assuming that I am not at fault I would dare to say that on a 2017 27" iMac running Monterey 12.5.1, SuperDuper and CCC cannot make a bootable drive.

Incidentally, Bombich states that Silicon Macs cannot be booted from any external SSD/HDD so if your internal drive fails you are scuppered.

No luck!

I have completely erased the T5 SSD and reinstalled the SuperDuper backup again but it still won't boot either from System Preferences or by holding down the option key at startup. It begins but never finishes.

Another old Crucial SSD with a bootable copy of Catalina boots perfectly.

I am wondering if the macOS 12.5.1 security update may be responsible . . . Apple trying to stop anything accessing the computer!

Thanks for the link.

I don't know whether it is me being stupid or the instructions that are very ambiguous (or just completely wrong!)

Does section 3 mean the volume you are going to copy the Mac drive onto . . . in other words the external SSD?

1. In the Disk Utility app  on your Mac, choose View > Show All Devices.
2. If Disk Utility isn’t open, click the Launchpad icon in the Dock, type Disk Utility in the Search field, then click the Disk Utility icon.
3. In the sidebar, select the volume you want to restore, then click the Restore button .
4. This is the volume that is erased and becomes the exact copy.
5. Click the Restore pop-up menu, then choose the volume you want to copy.
6. Click Restore, then click Done.