How to format bootable external SSD for Big Sur 11.6.2

Question

How to format bootable external SSD for Big Sur 11.6.2

I recently upgraded to a 2019, 5K 27" iMac with a view to driving it from a 1TB Samsung T7 through USB-C 3.2 or, if necessary, via Thunderbolt 3.

I formatted the T7 for APFS with Disk Utility and cloned my pristine OS with CCC.

On restart, Start-up manager could not recognise the disk although Disk Utility and CCC confirmed tasks were completed successfully. Much of the information I have gleaned is outdated. I am aware that power and cable choice is important and some users favour external power. Other users have downloaded OS Installers prior to cloning. A step I may have needed.

I simply want to achieve a bootable external Big Sur from the T7.

I seek advice from a user who has achieved that objective who may be kind enough to advise me regarding method and equipment suitable to my computer and OS.

iMac 27″, macOS 11.6

Posted on Dec 30, 2021 10:54 PM

Reply

Answer 1

Dec 31, 2021 5:26 AM in response to Jack-19

Jack, the whole installation went as smooth as silk. I found this article https://osxdaily.com/2021/02/18/how-redownload-macos-big-sur-installer-from-big-sur/

which included a really simple command line: softwareupdate --fetch-full-installer which places the installer in Applications. After installation the Mac restarted smoothly and the transfer of files was routine. Now the T7 is my permanent start-up disk. It seems Apple has refined and eliminated the previous Big Sur glitches in OS 11.6.2.

Thanks again for your quick response and an easy road map.

Cheers,

Reply

Answer 2

Jack-19

Level 8

46,272 points

Dec 31, 2021 5:29 AM in response to Australopithicus01

Australopithicus01 wrote:

Jack, the whole installation went as smooth as silk. I found this article https://osxdaily.com/2021/02/18/how-redownload-macos-big-sur-installer-from-big-sur/

which included a really simple command line: softwareupdate --fetch-full-installer which places the installer in Applications.

Glad it worked, but you could also use How to get old versions of macOS - Apple Support which accomplishes the same thing.

Jack

Reply

Answer 3

Jack-19

Level 8

46,272 points

Dec 30, 2021 11:06 PM in response to Australopithicus01

Welcome to the Apple Support Communities.

Please refer to How to Setup and Use an External SSD as y… - Apple Community.

If the Samsung SSD still doesn't work, return it for a recommended SSD in the User Tip.

Jack

Reply

Answer 4

ku4hx

Level 7

23,700 points

Dec 31, 2021 5:37 AM in response to Australopithicus01

Yep, Jack-19 wrote a great guide. Note however, you are not cloning a drive, you're installing an operating system onto the external drive.

I've been using CCC for years and for the last several months I've been communication with Mike Bombich about CCC and Monterey. Up through Big Sur 11.6.1 I could easily make bootable clones. With Monterey, that mostly came to a screeching halt. Bombich now recommends for Monterey no clones be attempted, but use the app in similar fashion as TimeMachine. In fact, what you get is a non bootable "clone" that is functionally a duplicate of TM but comes with far greater flexibility and more backup choices than TM. When I install a new OS, CCC's data "clone" is my choice now to create back ups and to migrate data. So far it has worked extremely well in both roles.

One oddity Mr. Bombich cannot explain: I CAN create bootable clones of our two MacBook Pros both running Monterey, but CANNOT create bootable clones on our three iMacs running Monterey. All are happily Intel machines.

Reply

Answer 5

Dec 31, 2021 5:29 PM in response to ku4hx

Thanks for the helpful comment. In reading options to creating a bootable external drive I read references to difficulties with CCC regarding Monterey and notably Early Big Sur. You will already be aware of these details but for the sake of a casual reader a few comments may be helpful. This updated article May 2021, article by Mike Bombich explained the situation at that time .https://bombich.com/blog2020/11/3/yes-you-can-have-bootable-backups-on-big-sur This was why I was a little surprised at my early CCC attempt failing. I look forward to a time when Monterey has the glitches ironed out.

Thank you for the note. It helps me appreciate what I am dealing with.

Best Wishes,

Tony.

Reply

Answer 6

Jan 2, 2022 1:03 AM in response to Jack-19

Hi Jack, this may be a little off topic but ku4hx has, I think, pinpointed an oversight I have made in copying across my previous Account files. The distinction between clone and operating system. I have finished up with 2 sets of Applications files, one in the normal location and a second in Library>System>Applications folder. All contents have the same Modified date. The Modification dates are 8 minutes apart.

The obvious reaction is to trash the older Applications folder but the OS system protects it.

Can you refer me to a correct process for safe deletion of protected files please? Or is erasure and reinstall the best approach?

If erasure is best, I have on my Macintosh HD two Mackintosh HD-Data volumes, disk 2s7 has 8.48GB used and disk 2s1 has 289.63 GB used. I am assuming the smaller disk containes my Home Account files as it has the House symbol visible next to the volume in Disk Utility. Before I make further errors I would appreciate clarification on how 11.6.2 distributes data. Under what conditions does 11.6.2 make separate volumes?

Any help or re-direction would be appreciated.

Reply

Answer 7

Dec 31, 2021 1:43 AM in response to Jack-19

Thank you Jack, just what the Doctor ordered. I don’t think you missed a beat in that outline.

Thank you very much and congratulations on writing such a clear set of directions.

Best Wishes,

Tony

Reply

Answer 8

Jack-19

Level 8

46,272 points

Dec 31, 2021 3:26 AM in response to Australopithicus01

You're welcome!

Jack

Reply

How to format bootable external SSD for Big Sur 11.6.2

Similar questions