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Bootable clone of Big Sur on Mac Mini M1?
- Thread starter winna
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I have done it successfully for my M1 MBA with both methods in this CCC article, using both a Samsung T5 USB, and a Envoy Express/WD SN750 NVMe Thunderbolt drive.
There are many threads here about problems making bootable externals, and the reasons why it works for some people and not others are not clear. It does seem that Thunderbolt externals are more likely to be successful than USB.
I have had failures as well as the successes. For me, the factors that worked were installing from a bootable USB 11.1 installer, and having the target external connected directly to the MBA not via a powered dock. I did not use reduced Security settings.
There are many threads here about problems making bootable externals, and the reasons why it works for some people and not others are not clear. It does seem that Thunderbolt externals are more likely to be successful than USB.
I have had failures as well as the successes. For me, the factors that worked were installing from a bootable USB 11.1 installer, and having the target external connected directly to the MBA not via a powered dock. I did not use reduced Security settings.
Thanks.
Unfortunately you can't just replace a faulty hard drive in a Mac Mini M1 so it would be great to boot from and external NVMe Thunderbolt drive and keep using the computer
Depending on what’s at fault, that might not work. The M1 Macs always use the internal SSD to start the boot process. If the SSD is faulty and can’t boot, then the only solution is to get it repaired.
If the problem is with the boot software, you can restore it with Apple Configurator 2 and another Mac.
If it is impossible to boot to a clone if the internal SSD has failed, it is rather a severe limitation of whole purpose of CCC clones, (though are either reasons for needing to).
I wonder if Mike Bombich of CCC is aware of this. I will ask him if you can give a source or link for this please.
Thanks
Might be difficult to track down, it was something I read on Twitter by one of the people working on running an alternative kernel. I'll look though.
This is what I found from a quick look through my browser history:
macOS 11.2 Beta 2 adds full custom kernel support
Edit: Read the section from Howard Oakley
I have emailed Mike Bombich and quoted the link and Howard Oakley's key paragraph:
"This ingenious new boot process does have consequences, though. Failure of internal storage means failure of the whole Mac, which can’t then boot from an external disk, which lacks the essential iSC and can’t provide 1TR either. I think this is already true for Macs with T2 chips, with their single security policy, rather than one for each bootable operating system as in the M1. I suspect it’s also, in part at least, responsible for the lack of an Internet Recovery Mode in M1 Macs"
Confidence in what he says is undermined somewhat by saying he thinks it is already true for T2 Macs. I can't help feeling that if T2 Macs have the same problem this topic would have blown up already. Even if Howard only means T2 Macs with the default no external boot policy, it would be well known and understood. M1 Startup Security options don't mention booting from externals which the T2 equivalent does, and as I said earlier, I can boot my M1 from externals with full security.
What he says might be true for M1 Macs but I don't think it can be for T2 Macs.
As far as I know, T2 Macs still use EFI. The M1 Macs do not. They use a custom boot loader. So I agree, it isn't likely that T2 Macs and M1 Macs boot the same.
I've used CCC for, well, I don't know how long. Almost as long as it's been around, and it's rare for Mike not to know something, and be correct about it. The fact that he's still trying to figure out what is going on here is an indication of just how complicated it's gotten to produce a proper clone these days.
I really hope this 'inability to boot from an external drive if the internal storage fails' turns out to be untrue, or at least ultimately fixed some way. That's a SNAFU of biblical proportions on Apple's part if accurate, because it's going to almost immediately eliminate Apple's hardware from any number of time-sensitive and mission-critical tasks where the ability to immediately boot from a recent clone and continue working is of upmost importance. Maybe Apple thinks people don't use their equipment for "real work." This is the type of thing that will help ensure it!
I really hope this 'inability to boot from an external drive if the internal storage fails' turns out to be untrue, or at least ultimately fixed some way. That's a SNAFU of biblical proportions on Apple's part if accurate, because it's going to almost immediately eliminate Apple's hardware from any number of time-sensitive and mission-critical tasks where the ability to immediately boot from a recent clone and continue working is of upmost importance. Maybe Apple thinks people don't use their equipment for "real work." This is the type of thing that will help ensure it!
I have a reply from Mike Bombich, very quickly as usual. He regards it as speculation at this stage, and that he doesn't intend to test by sabotaging his M1 MBA. He regards the Oakley statement as too broad, ie there might be some failures of the internal storage which would prevent booting an external, but that (eg) a software update which made the internal unbootable wouldn't prevent booting from an external.
If Mike can figure it out, that would be huge. And in my opinion, would warrant an upgrade release.
If something happens with my M1, I can use my iPad Pro to get my work done, although its not ideal. It would get me by until Apple fixed it or I purchased a new one.
If something happens with my M1, I can use my iPad Pro to get my work done, although its not ideal. It would get me by until Apple fixed it or I purchased a new one.
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Similar here, plus I hate booting from clones. So many apps have to be reauthorised, re signed in, sync with their clouds etc etc. My usage is not such that I need instant bootability. I use CCC clones as backups which can be used for migrating to new machines or drives. I appreciate that some do need instant bootability.
Does this mean that it will be possible to boot from a ccc clone? I have ccc clones for all my macs, they are superb!
You can do it now, as my post #2, but it is not a one step process. The Oakley comments you ask about raise the concern about whether a bootable clone will boot if the internal drive has a problem.
Yes but I need a one step process, let’s hope 11.2 will fix that. I run my old iMac from an external SSD
I have had an essentially cloned system (2nd install and migrate) to support a release and beta version of Big Sur.
The biggest problem these days is iCloud login. Apple has become more rigorous on a single system only being logged in once. You have to reauthenticate with all its iterations through other systems (Mac and iOS) which in the end made it a complete PITA. I also had trouble losing Watch unlock and not being able to re-establish it using all known hacks (delete sharing locks and hidden keychain keys etc.) I just deleted the std version and am just on 11.2beta, since BlueTooth is improved and everything worked.
The biggest problem these days is iCloud login. Apple has become more rigorous on a single system only being logged in once. You have to reauthenticate with all its iterations through other systems (Mac and iOS) which in the end made it a complete PITA. I also had trouble losing Watch unlock and not being able to re-establish it using all known hacks (delete sharing locks and hidden keychain keys etc.) I just deleted the std version and am just on 11.2beta, since BlueTooth is improved and everything worked.
Does this paragraph from this CCC article help at all? If so it is an explanation not a solution at this point.
"The System volume is not encrypted when FileVault is enabled on a Big Sur startup disk
This is not a bug, this appears to be a deliberate change on macOS Big Sur. When you enable FileVault on a Big Sur startup disk, the System volume member of the APFS volume group is not encrypted. Considering that this volume is identical on all Macs, encrypting its contents is not going to prevent someone from knowing what's on it, so the encryption does appear to be unnecessary. There is one undesirable effect of this change, however, regarding an encrypted, bootable backup disk. When you attach the device to your Mac, the System volume is mounted automatically, regardless of whether you unlock the associated Data volume. If you specifically choose to not unlock the Data volume, there are three results that range from confusing to annoying to alarming:- The volume appears to be mounted in the Finder, despite not wanting to mount it
- None of the data on the volume is accessible because the Data volume isn't mounted, so you might be led to believe that your data has been lost
- There is no apparent way in the Finder to get the Data volume unlocked and mounted
We have reported this issue to Apple (FB8918177) and we are currently awaiting a response"
I finally succeeded
I was enable to active FileVault, it did take some testing though (8 hours or so). Now I can just clone away whenever I want