Backing up iMac after partition, from a flash drive (USB)

[Michael Devereux]

I'd like to partition my iMac (i5 core, OS 10.13). I've backed up the entire system to a flash drive (USB). Can I safely partition the disk assured that the computer will now start up from the flash drive? Right now, with the flash drive plugged in to a USB port, the computer doesn't recognize the flash drive backup when I try to select " startup disc" in preferences. It only seems to permit starting up from the internal HD.

Possibly I need to install system 10.13 on the flash drive before backing up the iMac to that flash drive, no?

 

[Cory Cooper]

Hello.

-Is there a reason you want to partition the drive?
-How did you clone the iMac to the flash drive? It won't be bootable if done by simple drag and drop.
-What did you backup to the flash drive and how large is it?

C

 

[Michael Devereux]

Hello.

-Is there a reason you want to partition the drive?
-How did you clone the iMac to the flash drive? It won't be bootable if done by simple drag and drop.
-What did you backup to the flash drive and how large is it?

C

Thanks, Cory.

I want to partition the drive, to run old software, like Mathematica, in one partition. I'll try Parallels there, emulating OS 10.2 or 10.4, I hope. Backed up the current system, OS 10.13 to the flash drive, about 14 Gbyte. I've concluded, after considering lots of kluges, that I need to purchase an OS 10.13 install disc to perform the partition, then restore the OS 10.13 system from the flash drive.

Michael

 

[Cory Cooper]

OK, thanks.

-Parallels is an application, and you don't need to partition your drive for that, as you would install the older Mac OS in a virtual machine that is simply a document on your current partition.
-There isn't a 10.13 install disc available. It was a download from the App Store only. If you do find a disc, it is an illegal copy from a third-party and not Apple.

C

 

[Michael Devereux]

Thanks, Cory.