Booting an M1 Mac with a Big Sur disk taken from an Intel Mac

[Lars B.]

I currently have an Intel Mac mini with an external Thunderbolt SSD as the only drive (there is an internal SSD as well, but that one's empty and unused). The Mac is running Big Sur. Can I simply replace the Mac mini with the new M1 Mac mini, connect the external SSD and everything else currently connected to the Mac mini (power, screen, audio) and immediately continue working without any migration? Or will the M1 Mac mini be unable to boot from the Intel Mac's SSD?

 

[Lars B.]

Maybe my question was unnecessarily complicated.
Can an M1 Mac boot from a Big Sur disk created on an Intel Mac?

 

[MacUser2525]

Should work the machines will have access to the same files if up to date. There is no one version that only has intel code and another for the arm, Apple uses universal binaries for just this reason, both sets of code in the one binary file. They did the same with the PPC to intel change many years ago.

 

[hobowankenobi]

A good question. I have no idea yet, but my first hunch would be: no.

It depends on what Apple installs...

It may be everything gets installed, so yes, it will boot on any Mac that supports OS 11.
Or, based on hardware validation, only the platform-specific pieces are installed.

In bygone days, in a similar situation (booting to hardware different than that used for original install), if the OS did not boot, often one could do one of the following to resolve from the newer hardware:

1. Run the latest OS Combo updater (typically the same version and the installed OS), and it would install/fix/replace anything missing.
2. Run a full OS install—without erasing the drive—to install/fix/replace anything missing, leaving all user data, preferences, settings, in place.

Based on that history, I would be sure to clone the OS before proceeding, to be sure one could roll back...and then plug in and try to boot. If booting does not work, try step 1, and then if no luck, try step 2.

With a good clone virtually no risk of getting stuck with non-booting wonky OS.

As an alternative, one could do a TM backup too, and then use the Migration assistant to migrate/update the OS on the Mini, and then eventually clone that to the external....assuming there is enough space on the internal drive.

 

[MacUser2525]

A good question. I have no idea yet, but my first hunch would be: no.

It depends on what Apple installs...

Apple installs the operating system they ship, a dual boot capable one with universal binaries to support the transition. With it being this new you just have to make certain you have the latest version of it installed to avoid a potential situation where the newest hardware needs the newer files present to boot. Some of the time when it is releasing a new version of machine there is special build for its hardware. Then those changes are incorporated into the next release of the OS so any build after this can be used to boot the machine. But nothing before will be able to boot the machine as the support and machine IDs are not present in it.

 

[hobowankenobi]

Apple installs the operating system they ship, a dual boot capable one with universal binaries to support the transition. With it being this new you just have to make certain you have the latest version of it installed to avoid a potential situation where the newest hardware needs the newer files present to boot. Some of the time when it is releasing a new version of machine there is special build for its hardware. Then those changes are incorporated into the next release of the OS so any build after this can be used to boot the machine. But nothing before will be able to boot the machine as the support and machine IDs are not present in it.

Yes, agreed. Historically.

I was only guessing what might be...as per your point, occasionally a hardware driver was not available, and so an install on a different/older box would not boot on the latest hardware.

Hopefully this continues, but I do wonder as the Intel to M1 change is so substantial, so I would not be surprised if they take a different path. But only guessing, no M1 to test with yet.

 

[MacUser2525]

Yes, agreed. Historically.

I was only guessing what might be...as per your point, occasionally a hardware driver was not available, and so an install on a different/older box would not boot on the latest hardware.

Hopefully this continues, but I do wonder as the Intel to M1 change is so substantial, so I would not be surprised if they take a different path. But only guessing, no M1 to test with yet.

It is the same change and method used for PPC to intel. That worked rather well at the time with few problems as I remember going from a PPC operating system that could be tricked into booting on intel as they were developing it at the time. Leopard was the released hybrid with universal binaires and the original Rosetta to emulate the old PPC for people who needed that just like now with the second coming of it for the intel crowd. It ran flawlessly on my first hackintosh using the migration I did from my old dual G4 machine way back then. And now I remember that it was the next OS Snow Leopard that killed off the support for the PPC somthing to look forward to next year when they kill off intel.

 

[haralds]

I had trouble on my M1 with Big Sur installed on an external ssd with an Intel MacBook Pro also running Big Sur. This was after enabling multi-boot.

 

[hobowankenobi]

I had trouble on my M1 with Big Sur installed on an external ssd with an Intel MacBook Pro also running Big Sur. This was after enabling multi-boot.

Were you able to resolve it? If so, what was required to fix?

 

[Damian83]

I currently have an Intel Mac mini with an external Thunderbolt SSD as the only drive (there is an internal SSD as well, but that one's empty and unused). The Mac is running Big Sur. Can I simply replace the Mac mini with the new M1 Mac mini, connect the external SSD and everything else currently connected to the Mac mini (power, screen, audio) and immediately continue working without any migration? Or will the M1 Mac mini be unable to boot from the Intel Mac's SSD?

so, do u managed to simply switch ssd on the m1 mac?

 

[haralds]

I just tried to move a Ventura disk installed on my M1 PowerBook to my MacStudio.
I was able to boot after invoking the Startup utility. However, certain security features like Wallet or changing Security Policies never worked. I was also unable to install over it without completely wiping the disk. This was despite I set the disk ownership to a local user with the dialog initially appearing.
I finally resorted to creating a CCC backup and then wiping and reinstalling before restoring the CCC backup with the Migration Wizard. Since these were all SSDs it worked in a few hours (like 10!!!) This was a 2TB installation.

 

[Jack Neill]

M1 PowerBook

I was going to get the M1 PowerBook but it was out of my budget. I got a G5 PowerBook instead.

 

[Lars B.]

so, do u managed to simply switch ssd on the m1 mac?

Hi, no, it does not work, unfortunately. You have to use Migration Assistant to move data from the Intel installation to an M1 installation on another drive. It also doesn't work the other way round. External bootable SSDs created on an M1 Mac do not boot on an Intel-based Mac.

 

[quynhtrang]

Can anybody tell me if a Big Sur external disk installed on an M1 will boot an Intel machine?

 

[Damian83]

Can anybody tell me if a Big Sur external disk installed on an M1 will boot an Intel machine?

no. it was enough to spend at least 1m and read above instead of asking already 1000 times answered questions 😒

 

[quynhtrang]

no. it was enough to spend at least 1m and read above instead of asking already 1000 times answered questions 😒

OK, I read the above thread carefully and couldn't find an answer. I saw your post and reread the thread and still couldn't find an answer.

The original question was asking can an external boot disk created on an Intel Mac boot a M1 Mac. I know it doesn't work because I tried it before reading this thread.

My question was: Can a external boot disk created on an M1 Mac boot an Intel Mac?

 

[quynhtrang]

I'll answer my own question:

Can anybody tell me if a Big Sur external disk installed on an M1 will boot an Intel machine?

Apparently not. I tried with a Monterey install from my MacBook Air M1. Firstly I disabled boot security or something in the hold power button down install menu. It boots ok on the M1 but you get an error similar to a kernel panic on my 2019 iMac.

 

[Damian83]

OK, I read the above thread carefully and couldn't find an answer. I saw your post and reread the thread and still couldn't find an answer.

The original question was asking can an external boot disk created on an Intel Mac boot a M1 Mac. I know it doesn't work because I tried it before reading this thread.

My question was: Can a external boot disk created on an M1 Mac boot an Intel Mac?

Point of my thread was knowing if it was possible to have an “universal” disk that boots both systems (m and intel). Exactly like we did with only-intel macs. One disk that plugs and play and almost everything. Now, if the workaround to boot an intel disk on m1 was to make it first on m1, then problem would be solved. While isnt, as intel on m, or m on intel its the same, and thought it was pretty clear from above messages

 

[Lars B.]

OK, I read the above thread carefully and couldn't find an answer. I saw your post and reread the thread and still couldn't find an answer.

The original question was asking can an external boot disk created on an Intel Mac boot a M1 Mac. I know it doesn't work because I tried it before reading this thread.

My question was: Can a external boot disk created on an M1 Mac boot an Intel Mac?

I wasn't the one telling you to reread this thread, but you definitely did not read carefully, because in the post directly above your question, I wrote:

Hi, no, it does not work, unfortunately. You have to use Migration Assistant to move data from the Intel installation to an M1 installation on another drive. It also doesn't work the other way round. External bootable SSDs created on an M1 Mac do not boot on an Intel-based Mac.

Which is exactly what you were looking for.