Would be great if someone can check if it's possible to boot M1 Mac from an external drive like Thunderbolt or SSD.
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M1 Macs, boot from external drive possible?
- Thread starter sledgehammer89
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I did it. I went to recovery mode (hold power for about 10-15 seconds when booting). I went to Utilities > Startup Security Utility and changed to Reduced Security. I then went to Reinstall MacOS and selected my external SSD with an empty APFS volume (you can also erase the whole drive as APFS). About 1 hour later it was ready to setup after installing. I can switch without issue between the internal SSD and external SSD in System Preferences > Startup Disk.
I'm thinking it may be worth it to buy a 256GB M1 Mac and externally boot with an SSD that supports 1,000 or 2,000 Mbps read/write. I was doing that for years without issue with my 2013 iMac, but with a slower, cheaper SSD.
I'm thinking it may be worth it to buy a 256GB M1 Mac and externally boot with an SSD that supports 1,000 or 2,000 Mbps read/write. I was doing that for years without issue with my 2013 iMac, but with a slower, cheaper SSD.
It's doable. You just have to modify Start-up Security Utility settings. Similar to how it's done on T2 Macs.
Instead of having to reinstall Mac OS, is there a way to use Terminal commands to reduce security ?
I use the Thunderbolt 2 LaCie Rugged 1TB SSDs and works for the older Intel Macs..
I use the Thunderbolt 2 LaCie Rugged 1TB SSDs and works for the older Intel Macs..
I have recently changed to M1 MBA. However, my external ssd that is used to boot from my MBP 2017, could not perform the startup. The error message came out is “SDErrorDomain error 104”. Appreciate if you guys can give your inputs on how to work around it. (I could access this external drive).
External is on Big Sur? Boot to recovery mode by holding power about 10-15 seconds when starting up. Go to Utilities in the top menu bar, and then use Startup Security Utility to change to Reduced Security.
@Roy G Biv Is the external that you booted from a TB3 drive connected by TB3? There are quite a few discussions around about booting M1 Macs from externals and so far the only successful ones are with thunderbolt externals. E.G this one. I haven't seen one solid report of an external boot using a USB drive like a Samsung T5 or T7, unless yours is.
It wouldn't be surprising if at this point they will only boot from TB3 since macOS sees Thunderbolt externals and Mac internals as (completely?) equivalent, but not USB connected drives.
Also what M1 Mac did you do it on? I am bit puzzled because from your second para it sounds like you haven't got an M1 Mac yet. In that thread I linked there was one report of a USB boot with a DTK Mac, which doesn't have thunderbolt so I suspect is different in this topic from the production M1 Macs.
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Issue still persists with the same error message after changing to reduced security. Yes external is on Big Sur 11.0.1 same as that of my M1 MBA. I cannot afford to the erase the external ssd because it contains important data.
It’s a cheap SSD inside a cheap USB-A case. I have the 256GB / 16GB M1 Mini. I was saying others might want to save money by doing external boot on 256GB M1.
I can still switch with Mac on Big Sur 11.1, and external on 11.0.1. FileVault might be an issue for others; I don’t use it.
Thanks for confirming. I have since seen another confirmed report of booting from USB so there is a bit of mystery why some of us can't. I don't use Filevault either. The most recent report didn't apply Reduced Security in the System Security Utility.
I tried several things to get an external USB drive to boot with a fresh install of 11.1 and couldn't get it to work. It always failed sometimes with 1 minute left on the install. I could use the drive to create a boot installer using the createinstallmedia method: How to create a bootable installer for macOS
I wonder what the difference is? I tried everything I could think of including using an Intel Mac Pro. The USB install failed every time.
I have tried everything under the sun but so far nothing has worked. I even contacted Apple directly but they had no clue. I was able to install 11.01 on the external, but when I try to boot into it I can't get past the login screen. I tried every admin username I have ever used but it rejects them all. So I tried to install 11.1 on the external and it always gives me a "An error occurred while extending ownership to this volume". It always happens at the same place in the install process, with 52 minutes to go. Very frustrating because this same external drive worked flawlessly with a intel Mac mini. I really wanted to keep this M1 but it looks like I might have to return it. Not being able to boot into an external is a deal breaker.
Thanks Roy. Looks like I have to dent my pocket to get the TB3 external.
It allowed me to install 11.01 in recovery, but not 11.1.
Are we sure it's an enclosure issue?
It never occurred to me that my USB drive might be the problem. I’ll have to dig up another unused USB drive and see if that works better. I’m using an OWC USB 3.0 Envoy with a repurposed Apple SSD from an upgraded Mac Pro. It is a special version of the OWC Envoy designed to only work with Apple’s modified NVME SSDs.
I have tried two other USB drives. None are bootable with the M1.
Apple has a Configurator app that is supposed to help with the installation that I will try later.
Glad you were able to update. When I try to update in recovery it always crashes at 52 minutes to go, so I think I have no other option other than to return this M1 ?
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!!!
???
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!!!
???