So the trick is to move the Big Sur installer out of the /Applications folder? I'm going to try that. I can't try a USB-A port since I'm using a MacBook Air.Y E S !!! It IS possible! I've just accomplished it! Update to Big Sur 11.1 on your internal SSD first.
I have a WD My Passport 500Gb SSD plugged into the innermost (closest to the HDMI port) USB-A port (not sure it matters which USB-A port you use, but I'm using my exact results for reference), via the USB-A adapter that came with the USB-C cable for the drive. USB-C doesn't work, whereas USB-A does! Weird!
I formatted the drive as Untitled, APFS (plain; no encryption/case sensitivity), and GUID partition map. I booted up the M1 Mac Mini as normal (not in Recovery mode), and copy/pasted the Installer to the desktop (attempting to drag the installer to the desktop just creates an alias). I ran the installer. When it's done, the reboot process takes a little bit (be patient or just ignore it for awhile), but when it's done, you will get the language request. Time to set 'er up!
I am typing this response from my external drive install and... surprisingly, I'm not noticing any difference. Boot up takes a little longer... maybe a couple seconds? But the rest of the system seems just as fast as before.
So, know that, if you don't want to spend over $150+ on a Thunderbolt 3 drive, you don't HAVE to. Head to Best Buy and get yourself a nice WD My Passport 500GB USB-C drive for about $80 and use the USB-A adapter for it. Install will take a bit longer, but... IT WORKS!!!???
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M1 Macs, boot from external drive possible?
- Thread starter sledgehammer89
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I simply took that suggestion someone else posted. And, because everything worked, I have to assume it was part of the solution. Sorry that you don't have any USB-A ports to do this with. You may HAVE to simply get a Thunderbolt 3 drive, unless someone has a definitive answer elsehow. If anyone has this drive working on a Thunderbolt 3 port and all they did was move the installer to the desktop, the would be awesome. Of course, now that the drive is working on the USB-A port, I wonder if I can move it to one of the Thunderbolt 3 ports and... it should still work (boot), shouldn't it? ?
Testing right now. At about 14 minutes remaining I got an error that Untitled and Untitled-Data were not ejected properly. The installer is still going and is at 5 minutes though. Fingers crossed.
Same error. At the very end after "about a minute" remaining for about 5 minutes it failed with an error. So it looks like a USB-A port may actually matter.
Success here too:
M1 MBA on 11.1
What worked:
Booted from a 11.1 USB Installer.
Installed on an empty APFS volume on a USB Samsung T5
Migrated at end of install from CCC clone
Booted from new volume on T5
What didn't work:
Booted from a 11.1 USB installer
Tried to install onto a CCC data-only clone on a USB Samsung T5 to make it bootable.
Install started but gave "error occurred while extending ownership of this volume"
I am now pretty certain that my previous bad experiences were down to two things:
1. I didn't wait long enough while installing from Recovery.
2. When I thought it had 'hung' I shut down the machine with the power button. I suspect this is why I couldn't boot from the internal even though the install was being done to the external. Not beyond the bounds that it would have an adverse effect on the internal.
So I have validated the CCC restore using migration method, but not the install direct onto a data-only clone method. I have reported this to Mike Bombich maker of CCC.
M1 MBA on 11.1
What worked:
Booted from a 11.1 USB Installer.
Installed on an empty APFS volume on a USB Samsung T5
Migrated at end of install from CCC clone
Booted from new volume on T5
What didn't work:
Booted from a 11.1 USB installer
Tried to install onto a CCC data-only clone on a USB Samsung T5 to make it bootable.
Install started but gave "error occurred while extending ownership of this volume"
I am now pretty certain that my previous bad experiences were down to two things:
1. I didn't wait long enough while installing from Recovery.
2. When I thought it had 'hung' I shut down the machine with the power button. I suspect this is why I couldn't boot from the internal even though the install was being done to the external. Not beyond the bounds that it would have an adverse effect on the internal.
So I have validated the CCC restore using migration method, but not the install direct onto a data-only clone method. I have reported this to Mike Bombich maker of CCC.
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Interesting. I just get errors with a USB 3.0 drive. Maybe it needs to be at least USB-C or Thunderbolt. I installed to a USB 3.0 drive on my Mac Pro starting with a 11.1 USB Installer. That install went fine and I could boot the Mac Pro (2013 so no T2) from the external USB 3.0 drive. When I went to boot from the M1 MacBook Air, it seemed to be working. I was able to reduce security and set the drive as a startup with Startup Security. But when I tried to boot, I got an error that said the drive was damaged and needed to be reinstalled with Recovery. I tried that on the MBA but I just got the same error again. I really don't have a problem if USB 3.0 drives don't work but it should be documented because this has been very frustrating.
The key for me was using a bootable USB installer to install macOS onto the USB external, while booted from the M1 Mac.
I haven’t been able to test that scenario because my USB-C to USB-A adapters are too wide to use two at a time. I bought them when I had a four port MBP. I’ll have to get a different adapter to test.
Since I succeeded with a bootable USB installer (having previously failed installing from Recovery) I have tried again installing from Recovery and succeeded. So I wouldn't attach the same importance to a USB installer any more.
I'm still confused.
Has anyone been able to get Big Sur to boot with a standard USB-A or USB-C non thunderbolt 3 external drive on an M1 Pro or Air without using CCC?
Has anyone been able to get Big Sur to boot with a standard USB-A or USB-C non thunderbolt 3 external drive on an M1 Pro or Air without using CCC?
Yes. As above. CCC is of no assistance in doing this. What worked for me was first installing onto an external and at the end of the install migrating from the CCC backup up. I could have stopped without migrating. CCC did not help achieve a bootable install on the external. I was doing the test to see if the migration from a CCC backup worked as an extra step.
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Ok so it looks like to get this to work you need either
1. Native Thunderbolt 3 External SSD
2. Native USB-C External SSD
3. MAC MINI ONLY - Anything native USB-A not USB-C ports
What will not work (I've tried all 3 options below)
1. Thunderbolt 2 SSD via Thunderbolt 2 > USB-C Apple Adapter
2. SATA USB-A Connecter Via USB-A via USB-A > USB-C
3. USB-A native flash drive via USB-A > USB-C dongle.
If I'm missing anything, please let me know.
1. Native Thunderbolt 3 External SSD
2. Native USB-C External SSD
3. MAC MINI ONLY - Anything native USB-A not USB-C ports
What will not work (I've tried all 3 options below)
1. Thunderbolt 2 SSD via Thunderbolt 2 > USB-C Apple Adapter
2. SATA USB-A Connecter Via USB-A via USB-A > USB-C
3. USB-A native flash drive via USB-A > USB-C dongle.
If I'm missing anything, please let me know.
Yes, but that doesn't say HOW you got it working for you. Describe the hardware and steps you used to get it working, just like I did.I am on a M1 Mac Mini booting from an external ssd
Oh, as a second note, if I didn't post it to this thread, I am now running my drive off of USB-C. I was not able to create a bootable drive with it connected to the Thunderbolt 3 port, but after creating it on the USB-A port, I was able to remove the USB-A adapter and run it off the TB3 port, via the USB-C cable. Weird. ?
I think it's pretty self explanatory but here goes, Hook of your External HD ( I am using this external with USB- C https://prnt.sc/w65xyk) Open Disk Utility and reformat to APFS, Shutdown your Mac, Hold the power button on your Mac until you see the Startup Options, Select Options, Click continue under Options, Choose a user from the list who has administrative authority, Select next,
Log into the user account using the password, Select Reinstall macOS from the list, Choose the drive you want to reinstall macOS on, Now wait for the OS to reinstall, Then enjoy booting your Mac from an external.
For sure, this is what I'm trying to do. I would like to post a full walkthrough from start to finish on how to get this to work. The Native USB-A port is weird to me as is the Thunderbolt 3 part. As noted above I have a Thunderbolt 2 drive but that doesn't work. I might just spring for a native USB-C enclosure today to find out.
So I've gotten a Mac Mini M1 to boot from an external SSD via the USB-A port. (Samsung T7 2tb for reference) But now I can't get migration assistant to work. Says This Mac can't be used to migrate data. Any help would be appreciated.
I've confirmed that its booting from the external and I've set up iCloud. Just want to transfer my data from a Time Machine backup. Thanks!
I've confirmed that its booting from the external and I've set up iCloud. Just want to transfer my data from a Time Machine backup. Thanks!
Were you trying to migrate using Setup Assistant at the end of the install onto the external, or did you launch Migration Assistant from Utitities while booted from the external ?
I have successfully tested the Setup Assistant method twice with my M1 MBA (once migrating in from a CCC clone and once from a Time Machine backup up). I have not tried the second method.
Update:
I just got it to work on a M1 MBPro .?!?!?
Kingstong SSD > Seagate GoFlex USB 2.0 SATA to USB-A > Apple USB-A to USB-C Dongle.
Connect External Drive > Boot to Native M1 Recovery (NOT USB INSTALLER) > Erase External SSD > Install Big Sur on External SSD > Authenticate with Admin user on internal M1 11.1 Internal SSD = Install worked and I could boot to the External SSD.
Every single time in the past it would stop mid install with an error no matter what kind of dongle or ssd I used.
For reference this is what I tried below.
1. Thunderbolt 2 SSD via Thunderbolt 2 > USB-C Apple Adapter
2. Seagate GoFlex USB 2.0 SATA to USB-A via HP USB-A to USB-C Dongle
3. USB-A native flash drive via USB-A > Apple AVMultiport USB-C dongle.
Could it really be the Apple OEM USB-A to USB-C dongle? I mean it's possible, how else could this be working fine on the M1 Mac Mini using the built in USB-A port????
Going to run a few more tests. I will now use the Apple AVMulitport dongle and the HP USB-A to USB-C dongle to see if i can reproduce this.
I just got it to work on a M1 MBPro .?!?!?
Kingstong SSD > Seagate GoFlex USB 2.0 SATA to USB-A > Apple USB-A to USB-C Dongle.
Connect External Drive > Boot to Native M1 Recovery (NOT USB INSTALLER) > Erase External SSD > Install Big Sur on External SSD > Authenticate with Admin user on internal M1 11.1 Internal SSD = Install worked and I could boot to the External SSD.
Every single time in the past it would stop mid install with an error no matter what kind of dongle or ssd I used.
For reference this is what I tried below.
1. Thunderbolt 2 SSD via Thunderbolt 2 > USB-C Apple Adapter
2. Seagate GoFlex USB 2.0 SATA to USB-A via HP USB-A to USB-C Dongle
3. USB-A native flash drive via USB-A > Apple AVMultiport USB-C dongle.
Could it really be the Apple OEM USB-A to USB-C dongle? I mean it's possible, how else could this be working fine on the M1 Mac Mini using the built in USB-A port????
Going to run a few more tests. I will now use the Apple AVMulitport dongle and the HP USB-A to USB-C dongle to see if i can reproduce this.
I think it is just really buggy. So if you get lucky it works. If the bug is aggravated by using USB 2.0/3.0 instead of 3.1 or Thunderbolt, it gets really hard to figure out what's going on.
Oh for sure. The entire process is super buggy and like you said might be the root of all of our issues. For the next test I'm installing the same way as I did with the successful test but with - SSD > ThunderBolt 2 Dock > Apple TB2 to USB-C Dongle.
Booting an M1 Mac from an external disk: it is possible
eclecticlight.co
Merry Christmas to everyone!
Booting an M1 Mac from an external disk: it is possible
If you’ve been unable to create a bootable external disk to use with your M1 Mac, this explains what you need and its limitations and quirks.
eclecticlight.co
Merry Christmas to everyone!
Hey Folks,
I've had the same issues/problems and even had a phone Call with Apple. The Apple Support Guy told me to change the Security Settings to the "Lower Security"-Setting and then reinstall Big Sur on the External SSD and also told me that the installation is bootable on an Intel Mac which should then be used to setup an admin account.
Don't be fooled by this sh*t. It does not work and it also makes no sense.
By the way: I have a Macbook Air M1.
That's how it is:
- It is NOT possible to boot an Intel Installation (on an external SSD) with a M1 Mac.
- It is NOT possible to boot a M1 Installation (on an external SSD) with an Intel Mac.
- It seems it it not possible to boot from external USB SSDs.
What worked was getting a Samsung X5 2TB Thunderbolt 3 SSD. Works flawlessly. Migration Assistant also works. It's the only option right now. Did tests with various SSDs, forget it.
I've had the same issues/problems and even had a phone Call with Apple. The Apple Support Guy told me to change the Security Settings to the "Lower Security"-Setting and then reinstall Big Sur on the External SSD and also told me that the installation is bootable on an Intel Mac which should then be used to setup an admin account.
Don't be fooled by this sh*t. It does not work and it also makes no sense.
By the way: I have a Macbook Air M1.
That's how it is:
- It is NOT possible to boot an Intel Installation (on an external SSD) with a M1 Mac.
- It is NOT possible to boot a M1 Installation (on an external SSD) with an Intel Mac.
- It seems it it not possible to boot from external USB SSDs.
What worked was getting a Samsung X5 2TB Thunderbolt 3 SSD. Works flawlessly. Migration Assistant also works. It's the only option right now. Did tests with various SSDs, forget it.
Booting on external drive M1 Mac
For background, I’m Coming from 2018 Intel Mac Mini using an external Plugable Thunderbolt 3 NVMe SSD as my boot drive.
I purchased the M1 Mac Mini in the 16gb with 256 SSD thinking I could save the $400 and keep using my external drive. Boy I did not know what apple had in store for me...
After spending hours unsuccessfully trying to use the drive, I turned to this forum for help. Like many I found help and got as far as booting into the drive but unable to clone or backup from time machine to instal all my apps, files, profile, etc. searing other forums, and piecing advice together, I was finally happily running the M1 Mac mini with my external drive as intended.
Her is how I ended up getting it to work:
I Setup new M1 Mac Mini using internal drive. Used migration assistant to clone external intel drive from my 2018 Mac mini to the internal M1 drive. I then booted into M1 internal drive.
Since the M1 Mac can not use a boot drive that was created from an intel Mac, I had to erase the external drive using disc utility and reformatted to APFS and GUID. You have to do this from your M1 Mac. This is a critical step, intel boot drive won’t work on M1 Mac.
Restarted M1 Mac using the new system restore start up options (hold down power button on the Mac mini until options menu loads) from there I had to change security settings to “low security”on the internal M1 drive. (If you don’t do this, migration assistant won’t work) Then instal fresh copy of Big Sur onto external drive using recovery menu within the startup options screen. (You must instal Big Sur from this menu, you can’t instal it through the App Store).
After an hour or so, the M1 Mac booted from the external drive and I was presented with language selection screen. (Be patient, system will restart several times) From there I continued setup and used migration assistance to clone internal M1 drive to the “new” external drive.
Missing any of the steps above will break the chain that allowed this to work.
Good Luck!!
For background, I’m Coming from 2018 Intel Mac Mini using an external Plugable Thunderbolt 3 NVMe SSD as my boot drive.
I purchased the M1 Mac Mini in the 16gb with 256 SSD thinking I could save the $400 and keep using my external drive. Boy I did not know what apple had in store for me...
After spending hours unsuccessfully trying to use the drive, I turned to this forum for help. Like many I found help and got as far as booting into the drive but unable to clone or backup from time machine to instal all my apps, files, profile, etc. searing other forums, and piecing advice together, I was finally happily running the M1 Mac mini with my external drive as intended.
Her is how I ended up getting it to work:
I Setup new M1 Mac Mini using internal drive. Used migration assistant to clone external intel drive from my 2018 Mac mini to the internal M1 drive. I then booted into M1 internal drive.
Since the M1 Mac can not use a boot drive that was created from an intel Mac, I had to erase the external drive using disc utility and reformatted to APFS and GUID. You have to do this from your M1 Mac. This is a critical step, intel boot drive won’t work on M1 Mac.
Restarted M1 Mac using the new system restore start up options (hold down power button on the Mac mini until options menu loads) from there I had to change security settings to “low security”on the internal M1 drive. (If you don’t do this, migration assistant won’t work) Then instal fresh copy of Big Sur onto external drive using recovery menu within the startup options screen. (You must instal Big Sur from this menu, you can’t instal it through the App Store).
After an hour or so, the M1 Mac booted from the external drive and I was presented with language selection screen. (Be patient, system will restart several times) From there I continued setup and used migration assistance to clone internal M1 drive to the “new” external drive.
Missing any of the steps above will break the chain that allowed this to work.
Good Luck!!
Do you know which make and model, so we can add it to the list of known working drives?