M1 mac external boot

RalvisM1 wrote:

I was unable to install Big Sur on my T5 External on my Macbook Air with the bare install method.

I tried the CC method of copy an existing data and then running Big Sur Install.and it works fine. Thank You Carbon Copy.

Be aware that I have seen multiple reports of the Samsung T5 working

at first but eventually become unbootable.

Full instructions are posted here;

https://discussions.apple.com/thread/252222611

It actually seems like it's faster from the external boot drive than the internal drive.

I was unable to install Big Sur on my T5 External on my Macbook Air with the bare install method.

I tried the CC method of copy an existing data and then running Big Sur Install.and it works fine. Thank You Carbon Copy.

Update on External Boot

Last night I changed to my 1 TB Sata SSD with my M1 Macbook Air. This morning after doing my banking etc I decided to try my T5 Samsung again as my Boot SSD. Following the procedure I previously used it works, as I am writing this while running on the T5. The only thing I would add is that it took 3 tries to change the startup disk to the T5 from my internal SSD. You should not use the restart function, keep changing until you can lock the T5 and it becomes coloured, then shut down. Then restart and it should run.

If anyone has had success with the Samsung X5 could you let me know.

Thanks

Just use reduced security

I don't see why it wouldn't work unless the external drive does not have Big Sur. Anything below will not work on a M1

Qwerty_God wrote:

Can M1 mac external boot? (Because it is much cheaper)

And much slower!

Ran Blackmagic Speed Test on my brand new MacBook Air

(8 core GPU variety) and the SSD reads and writes were

nearly 3 GB/sec.

There are Thunderbolt 3 SSD drives nearly as fast but they cost

more than built in Apple SSD.

MyApple8MyPC wrote:

......

Same issue as before, where it does not assign an admin account, so you can't login.

....

Sounds a lot like the issue I was having although it seems my

sequence of events is slightly different. I get kicked into recovery

when booting the external drive and request a verification. I

enter the password for the admin presented then says it can't verify.

Next, if I go into the Startup Security and try to change the settings

on the external drive, it says no admin account found.

I am not sure it is totally an M1 issue but also a Big Sur issue (in fact maybe

a major portion) that is not properly installing. If one were to do an external

install on an Intel machine, assuming it works, it would be interesting

to do a side by side comparison of the installs.

Something I was thinking of trying but not sure if it can even be done,

try and do a Time Machine restore to the external drive and see if that

works. Normally, doing it to the internal drive will restore a complete

functional system. So, if one could do that to an external, one would think

it would boot.

I also had some sporadic success with USB enclosures but the TB3 is solid.

That was one of the things I saw as well, one time. I tried four installs

from recovery, each resulted with different problems and each time,

downloaded the full installer over the internet.

Perhaps wait for next Big Sur update and see if that does anything.

As it stands, it seems external booting is not ready for prime time

on M1 Macs, or at the least is very flakey.

Jeffdoehring wrote:

I don't see why it wouldn't work unless the external drive does not have Big Sur. Anything below will not work on a M1

If you follow the entire thread, you will see many that cannot get Big Sur

to boot on an external drive with an M1 machine.

tbirdvet wrote:

By the way I tried using my WD Black M2 drive in a USB-C enclosure which of course is slower than the TB3 and it would not complete the installation so speed or port compatibility may be an issue.

There are some that swear they are booting into the M1 with USB enclosures.

tbirdvet wrote:

I think in the future I will try the normal process and just do the update after booting from the external drive. It should work fine as that is what I do on my other Mac (non M1 design) and it works fine.

According to the CCC website (and Apple) you should be using Migration Assistant to copy an intel backup to a M1 backup.

https://support.apple.com/en-us/HT204350

https://bombich.com/kb/ccc5/creating-and-restoring-data-volume-backups#install_macos

https://bombich.com/kb/ccc5/help-my-clone-wont-boot

It looks like your original way of doing it is the best way;

I spent sometime this morning Googling this whole issue and have

seen a whole mix of success and failures over a seemingly wide range

SSD/enclosure and install methods. There also seemed to be a whole

range of failure modes as well.

All of this seems to point to that a pretty vital feature of being able

to install and boot macOS externally on M1 Macs was either not thought out

thoroughly, or just badly implemented, or rushed out too soon or basically

made too many changes to the whole process at once to test and deal with.

Pick one that suits your fancy. As an aside, there are some people just trying

to re-install on the main drive that cannot get it working.

The last job I had, the product manager made it a point that it doesn't

matter how buggy the system or added features were as long as there

was a bomb proof method to start over!

As for my next step, it will wait until after the holidays as the Christmas

budget has been used up.

To all here, have a safe and happy holiday!