Clone won't boot

[gbdoc]

Using a MBAir M2, Monterey 12.5.1, SD 3.6.2, external Toshiba HDD connected via hub’s USB 3 Superspeed. I can make a clone (which I assume is OK), but can’t boot from it - as I was able to on previous Intel Macs. When I try to boot from the clone, the Mac’s power shuts down briefly and the HDD loses power, and when the Mac re-boots and the HDD gets power again, it seems that the clone doesn’t get mounted quickly enough (or something similar) for the Mac to boot from it. It tries again and again, but never boots. Am I missing something? Is there a solution?

If I needed to simply repopulate the Mac from the clone I could probably use Migration Assistant, but if the Mac’s drive got so corrupted that it wouldn’t boot, I wonder if the clone would ultimately boot - something I obviously haven’t tried?

[dnanian]

Since you cannot restore the OS into an Apple silicon Mac, you would always fully restore by installing the OS from recovery/network recovery and then selecting the copy when prompted to restore.

A bootable copy, made with "Erase, then copy", is a replication of the source, made by Apple's tools (since 3rd party apps are not allowed to copy the OS). It's as close as possible to the source. I fit's not booting, it may be that the drive is too slow or not fully compatible: I would suggest a WD MyPassport SSD (which is about $120 for 1TB). I think you're more likely to get satisfaction with that.

I would also try booting in Safe Boot from the backup to see if that works.

[gbdoc]

Thanks, Dave, but some of what you say is a bit above my head; I'm simply interested in whether/how I can boot from the clone with my M2 MBA. (The Safe Mode trial was unsuccessful with the Toshiba drive I'm now using.) I'm willing to buy another backup drive as you suggest (the 1TB WD MyPassport SSD is in fact EU246.99), but first I want to be sure. Do you have an M2 Mac and such an external drive and can you boot from the clone?

[dnanian]

I do not yet have an M2 Mac, although we've received very few reports of problems with them. Just recognize that we - as in SuperDuper - cannot change the way the copy of the OS is made. It's made with Apple's own tool, and if there are problems booting that can't be resolved with a different drive, it's a bug of Apple's we cannot fix...they have to do so.

[gbdoc]

Good, and I*m glad I asked. For now, I*m content that I have a clone I could repopulate from. Once you have an M2 Mac and have tried it, or someone with experience could answer this thread, I*d appreciate the information. Thanks.

[mmurray]

Originally Posted by gbdoc

Good, and I*m glad I asked. For now, I*m content that I have a clone I could repopulate from. Once you have an M2 Mac and have tried it, or someone with experience could answer this thread, I*d appreciate the information. Thanks.

Hi gbdoc,

I have the same setup as you but backing up to a Sandisk, Extreme Pro 1 TB. Like you I can't get it to boot and the description sounds similar. I'm happy enough knowing I can use Migration Assistant if I need the data. In fact that is how I set up the MacBook Air M2 in the first place. So I was just ignoring the issue for now. I guess now that Monterey 12.6 is out I should do an Erase / Install and try the whole thing again. I'll post the results back here if I do that.

Regards Michael

[gbdoc]

Originally Posted by mmurray

Hi gbdoc,

I have the same setup as you but backing up to a Sandisk, Extreme Pro 1 TB. Like you I can't get it to boot and the description sounds similar. I'm happy enough knowing I can use Migration Assistant if I need the data. In fact that is how I set up the MacBook Air M2 in the first place. So I was just ignoring the issue for now. I guess now that Monterey 12.6 is out I should do an Erase / Install and try the whole thing again. I'll post the results back here if I do that.

Regards Michael

Thanks for the feedback, Michael. So it sounds like re-booting from the clone isn*t currently possible on M2 Macs using Monterey, as I have (or before), and the problem won*t be solved by using a different backup medium; I have my theories, but I*m not sufficiently tech-versed to offer them. Obviously, I hope this can be changed in the future, but for now repopulating with Migration Assistant (which, luckily, I haven*t yet had the need to try, and hope I never will) seems to be the only alternative.

[dnanian]

I'm not sure what your "theories" would be here, but boot issues are, as of Big Sur, entirely in Apple's court - no 3rd parties can copy the OS, nor can they affect boot. There could be hardware issues, software issues, etc.

One thing to try, just to see if it works in a basic sense, is to install the OS on the drive on its own. If that boots, then a copy should boot as well. If not, well...

[gbdoc]

My main theory is that when I tell my Mac to boot from the external drive, it shuts down briefly and loses power before the re-boot begins. I assume that’s normal behavior. Upon regaining power and beginning to re-boot, the Mac responds more quickly than the external drive, so that’s the one which boots. I first suspected that that happens to me because my external is an HD, which may take a bit to spin up to speed, but mmurray, above, has the same result using an SSD, which is faster, so that doesn’t seem to be the issue.

Your answer suggests that neither an SD nor any other clone can’t contain the OS. That means to me that SD clones are not now nor will ever will be bootable, unless the 3rd-party utility would/could also install the OS on it. Correct? Is that do-able? Sounds like something you might consider for SD! 4. 🤞

My other theories boil down to the certainty that there is another explanation which only better-versed people could understand, which may or may not be correctable.

But, Dave, before I start to fool around with my backup drive (installing the OS on it), which contains my SD clone and a Time Machine, and works fine otherwise and is the only one I have, I think I’ll wait until you get an M2 Mac yourself (you will, sooner or later, I’m sure) and try this out, and report on your results.

[dnanian]

That's not what that means. It means we have to use the replicator to copy the OS. The OS has been copied by SuperDuper with "Erase, then copy" as detailed in the blog post about this.

Installing the OS on the backup doesn't change how it boots...the replication has effectively already done that. The OS is there.

Apple needs to fix their boot bugs. Nothing and no one else can do this 'for them'.

[dnanian]

Another thing to check - eliminate the hub and see if that helps...or, perhaps, try an external SSD. Neither may work (Michael is using an SSD), but it's something to try.

Note, too, that more recent OS versions may help as well, since Apple is releasing various fixes.

[mmurray]

Originally Posted by mmurray

Hi gbdoc,

I guess now that Monterey 12.6 is out I should do an Erase / Install and try the whole thing again. I'll post the results back here if I do that.

Regards Michael

Just following up on this. I never did check after 12.6 but I just installed Venture 13.1 and did an Erase and Backup with SuperDuper 3.7.2 to my external SSD. The SSD shows up in System Preferences and also when using "Startup Options" on boot. But when I try to boot with it I get about 5 mm of the progress bar and it quits. When I had chosen from System Preferences the failure seems to be it tries over and over again until I reboot with the power button and when I used the "Startup Options" it seemed to fail by switching to the internal SSD which boots.

As I said before I'm happy that I've got the data on the data volume and if I ever needed it I would just use Migration Assistant anyway so I don't need the option of booting anyway.

Regards Michael

[dnanian]

Have you tried Safe Boot when booting from the copy?

Apple has definitely been doing *something* to try to fix some of the Ventura bugs here - sometimes, reinstalling the OS over the backup will allow it to boot on Apple silicon. But they have more to fix.

[mmurray]

Originally Posted by dnanian

Have you tried Safe Boot when booting from the copy?

Apple has definitely been doing *something* to try to fix some of the Ventura bugs here - sometimes, reinstalling the OS over the backup will allow it to boot on Apple silicon. But they have more to fix.

Thanks! I just tried Safe Boot and it made no difference. I haven't tried reinstalling the OS over the backup yet.

[gbdoc]

I just found this recent article on Macworld, *How to start up your M1 or M2 Mac from an external drive* https://www.macworld.com/article/331...nal-drive.html. He says it can be done. I*m loathe to try it myself (not lazy, but I don*t have time to spare on what might ultimately be futile, and I don*t want to risk messing up my external drive which is partitioned for a clone + Time Machine) until you, Dave (who may have an M2 Mac by now), tests this and reports your results.