Cannot Boot from External SSD 1/M1

[Mac... nificent]

Hi, I bought the new Mac Mini M1 and would like to use it with a external 1TB SSD. I recently bought a 2018-2019 Mac Mini and was using my external SSD just fine with it, but now with the M1 it is having all kinds of connectivity issues. I thought I would just plug it in the M1 and it would work, since it has the same OS version as the internal SSD, but it wouldn't let me. It said I needed to reinstall 11.01 all over again, so I tried, but it got halfway and then said there was an error and it stopped installing.

It then said I had the wrong version of macOS, even though the internal SSD had the same exact version (11.01).

So I formatted my SSD and reinstalled 11.01 onto it. Guess what, yep, you guessed it, it says I can't use it because it needs to be "updated" - even though it is the current version of macOS (11.01).

BTW, I tried the Startup Security Utility as shown here;

https://support.apple.com/en-us/HT208198

but there was no external drive option.

How can I get this M1 to boot into the external SSD?

 

[bradbomb]

Sorry, I don't have an answer to your problem as I do not have an M1 Mac, but I would suggest changing the subject to "Cannot Boot from External SSD 1/M1". The way it's written suggests that external SSDs would not mount.

Now as to your problem, out of curiosity, how is the SSD formatted? APFS or HFS+, GUID vs MBR?

 

[Mac... nificent]

APFS

 

[haralds]

You do need to enable the relaxed security option in startup utility that changes the Security profile.
I was unable to boot macOS Big Sur installed on an Intel machine.

 

[Mac... nificent]

You do need to enable the relaxed security option in startup utility that changes the Security profile.

That option does not work!

It tells you to update Big Sur, but when you try it only crashes mid way. Tried several times with several drives.

 

[Quackers]

Have you run software update recently?
I ask because there might be an update to Big Sur 11.1 which may upgrade your firmware as well.
In the screenshot you show are there only the two options visible? There is not a third option "No security"?
Maybe you need a firmware upgrade, if there is one.

Upon further reading it seems you may have to disable SIP too using the terminal command
csrutil disable
This might give you the third option.
Though you need to check that this is necessary before you do it.
SIP would presumably need re-enabling afterwards with
csrutil enable

 

[alien3dx]

Sorry, I don't have an answer to your problem as I do not have an M1 Mac, but I would suggest changing the subject to "Cannot Boot from External SSD 1/M1". The way it's written suggests that external SSDs would not mount.

Now as to your problem, out of curiosity, how is the SSD formatted? APFS or HFS+, GUID vs MBR?

i rather said it boot , mount more on making the drive accessable.I'm waiting to test same thing on 24th when available m1 here before purchase

 

[Mac... nificent]

Have you run software update recently?
I ask because there might be an update to Big Sur 11.1 which may upgrade your firmware as well.
In the screenshot you show are there only the two options visible? There is not a third option "No security"?
Maybe you need a firmware upgrade, if there is one.

Upon further reading it seems you may have to disable SIP too using the terminal command
csrutil disable
This might give you the third option.
Though you need to check that this is necessary before you do it.
SIP would presumably need re-enabling afterwards with
csrutil enable

Yes, software update has been run and it says I have the latest version. In fact, ironically, the external drive has a newer build of 11.01 than the internal drive does (internal drive has build 20B29, external drive that was just installed has build 20B50).

There is no third option, and there is no section for external drives like the intel version had. Others on the Apple forum have reported the same thing.

Terminal will not allow us to run csrutil disable.

 

[Quackers]

Yes, software update has been run and it says I have the latest version. In fact, ironically, the external drive has a newer build of 11.01 than the internal drive does (internal drive has build 20B29, external drive that was just installed has build 20B50).

There is no third option, and there is no section for external drives like the intel version had. Others on the Apple forum have reported the same thing.

Terminal will not allow us to run csrutil disable.

It won't let you disable SIP on a running system.
To disable SIP you need to boot to the recovery environment then choose Terminal from the Utilities menu
Type the command and press enter
Type "reboot" (no quotes) and press enter

System will reboot and then you can re-enter the Startup Security Utility again.
The new options should be there.

 

[Mac... nificent]

It won't let you disable SIP on a running system.
To disable SIP you need to boot to the recovery environment then choose Terminal from the Utilities menu
Type the command and press enter
Type "reboot" (no quotes) and press enter

I have tried that but it won't let me run it because it is asking for a admin user. When I type in my admin name it says no user available.

 

[Quackers]

That's curious! You don't get options? Or are you the only user/admin?
It doesn't ask for the password at all?

 

[Mac... nificent]

That's curious! You don't get options? Or are you the only user/admin?
It doesn't ask for the password at all?

It first asks you which drive you want to apply it to. Then it reminds you what disabling the utility does. Then (sometimes) it asks you for your password. When I type it in it says the password was correct but disabling failed. I have tried this several times. Sometimes it asks for the admin name first. When you type it in it says 'unknown'.

I am the only admin/user.

 

[Quackers]

I see, thanks.
I've wondered about something similar before when there are 2 or more OSes on the same computer.
Maybe it gets a bit mixed up and is unsure which recovery environment it's in.
It's odd, for sure.

 

[panjandrum]

I have now tried several times to create a bootable external drive on M1 machines with no luck. I have successfully enabled (both of the) "Reduced Security" settings, and I am able to select the external SSD and proceed with the install. However after the install 'complete' I am left with a drive that boots back into the installer and claims that there were problems with the OS and that I need to reinstall. Rinse. Repeat.

Has anyone gotten an M1 to install and boot off an external drive? If so, how? (I see reports that possibly we need to disable system integrity protection, but if so I would have expected an error message somewhere along the line, and this was not necessary on T2 Intel Macs. So I'm holding off on that until I see more confirmation.)

 

[Quackers]

I have now tried several times to create a bootable external drive on M1 machines with no luck. I have successfully enabled (both of the) "Reduced Security" settings, and I am able to select the external SSD and proceed with the install. However after the install 'complete' I am left with a drive that boots back into the installer and claims that there were problems with the OS and that I need to reinstall. Rinse. Repeat.

Has anyone gotten an M1 to install and boot off an external drive? If so, how?

Can you read the contents of the external drive?
Are the main 4 folders present (system,library etc)?
Is the system folder empty?
It was suggested in another thread that the install may not include the necessary files from the system partition.
Folders, yes, but contents, no.

 

[honestone33]

I don't have an M1 Mini (not yet, anyway), but do have a late 2018 Mac Mini Core i5 machine. It is currently using the latest version of Catalina. I recently purchased this 1 TB External SSD:

Portable SSD T7 USB 3.2 1TB (Gray) | Samsung US

www.samsung.com

I partitioned it with 3 partitions: one formatted as APFS, 145 gig in size, and named Big Sur. The other 2, each formatted as HFS+, and they contain movies on one, and TV series on another. The SSD came with 2 cables, and I am using the cable that can attach to one of the USB-C ports on the Mini.

On Monday, I downloaded and installed (clean, fresh installation) V11.1 of Big Sur, then migrated files, folders, settings, apps, etc. from the internal SSD on the Mini. I have been running Big Sur from that SSD for 3 days now, and it works well.

Again, not an M1 Mini, but I never had V11.0.1 of Big Sur (or any other prior version). Maybe try a clean, fresh installation of V11.1 onto your external SSD. I believe some others have been successful doing that.

 

[Quackers]

I think the successful ones may have been using a thunderbolt drive/connection.

 

[honestone33]

On my Mini, the connection is Thunderbolt 3 (USB-C).

 

[Mike Boreham]

I have now tried several times to create a bootable external drive on M1 machines with no luck. I have successfully enabled (both of the) "Reduced Security" settings, and I am able to select the external SSD and proceed with the install. However after the install 'complete' I am left with a drive that boots back into the installer and claims that there were problems with the OS and that I need to reinstall. Rinse. Repeat.

Has anyone gotten an M1 to install and boot off an external drive? If so, how? (I see reports that possibly we need to disable system integrity protection, but if so I would have expected an error message somewhere along the line, and this was not necessary on T2 Intel Macs. So I'm holding off on that until I see more confirmation.)

Thunderbolt not needed, disable SIP not needed. I don't believe reduced security startup is needed either though I had it reduced...in this thread. Mike Bombich CCC maker says reduced security not needed.

 

[bradbomb]

Wait, dumb question here. Which machine did you use to install Big Sur on the SSD? The Intel Mini or the M1 Mini? Maybe the SSD needs it to be setup from the M1 machine as the Big Sur install file might different for M1 macs and Intel Macs.

 

[Mike Boreham]

Wait, dumb question here. Which machine did you use to install Big Sur on the SSD? The Intel Mini or the M1 Mini? Maybe the SSD needs it to be setup from the M1 machine as the Big Sur install file might different for M1 macs and Intel Macs.

It does...did all from the M1 MBA. I don't think an install made on an Intel will boot a M1. Not sure that missing files are the issue, but the install from an M1 asks questions about ownership at the start, which I don't think an install on an Intel does. Not 100% about this. But in another forum a guy tried installing from an Intel Mac and it didn't boot. Repeated from his M1 and it did.

 

[Luposian]

I have now tried several times to create a bootable external drive on M1 machines with no luck. I have successfully enabled (both of the) "Reduced Security" settings, and I am able to select the external SSD and proceed with the install. However after the install 'complete' I am left with a drive that boots back into the installer and claims that there were problems with the OS and that I need to reinstall. Rinse. Repeat.

Has anyone gotten an M1 to install and boot off an external drive? If so, how? (I see reports that possibly we need to disable system integrity protection, but if so I would have expected an error message somewhere along the line, and this was not necessary on T2 Intel Macs. So I'm holding off on that until I see more confirmation.)

I bought a WD My Passport 500GB SSD for my M1 Mac Mini. Update internal SSD to Big Sur 11.1. Connect USB-A adapter to USB-C cable for My Passport drive. Plug into USB-A port. Format as untitled, APFS (plain), GUID partition map. Copy/paste Big Sur 11.1 installer from Applications folder to Desktop. Drag/drop only creates an alias. Run installer. At end, it will reboot. Be patient or ignore it for awhile. It will come up at language request screen. You’re ready to go!

 

[Mac... nificent]

Which machine did you use to install Big Sur on the SSD?

The installation of Big Sur isn't the issue. The issue is that once the drive boots up and loads into the desktop, it asks you to log in as the admin. The problem is that there is no admin assigned, so you're stuck at the desktop login page.

From what I've read there is a file called AppleSetupDone that if you can remove it the system will log you back into the Welcome page where you can set up the Admin account again, but I can't locate this file, so I can't remove it. Below is a screenshot of what it looks like. I have two bootable drives, one is a traditional drive, and one is a SSD, and they both come to this same screen;

 

[panjandrum]

I bought a WD My Passport 500GB SSD for my M1 Mac Mini. Update internal SSD to Big Sur 11.1. Connect USB-A adapter to USB-C cable for My Passport drive. Plug into USB-A port. Format as untitled, APFS (plain), GUID partition map. Copy/paste Big Sur 11.1 installer from Applications folder to Desktop. Drag/drop only creates an alias. Run installer. At end, it will reboot. Be patient or ignore it for awhile. It will come up at language request screen. You’re ready to go!

So weird. I'm essentially doing the same thing (Samsung SSD and MacBook Air, but I'm not trying to do anything unusual here). One thing however, is that I've been trying the install from recovery mode, rather than downloading the Big Sur installer to the bootable OS on the internal drive and initiating the installation from there. I'll have to give that a try and see if that makes a difference.

 

[alien3dx]

any news if here existing os in external success ?