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Install mac OS on external SSD

Hi,

I am having iMac 27' 2017 model with fusion HDD.

My question is:


Instead of using fusion drive, can i connect external SSD and install Mac OS on that ?

Will this work? Also will my warranty be void if i do this workaround ? And cons of using this approach ?


Regards

Siddharth

iMac 27" 5K, macOS 10.14

Posted on Jul 16, 2019 1:30 PM

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Question marked as Top-ranking reply

Posted on Jul 16, 2019 2:33 PM

Yes it will work just fine. In fact, a lot of folks with slower HDD Mac are doing just that. For the best results, you will want to startup in macOS Recovery, Format the external SSD and Install macOS onto the external SSD. Then you can startup from the SSD and migrate your data from either the internal Fusion drive or your Time Machine backup during the initial setup.

4 replies
Question marked as Top-ranking reply

Jul 16, 2019 2:33 PM in response to siddharth2604

Yes it will work just fine. In fact, a lot of folks with slower HDD Mac are doing just that. For the best results, you will want to startup in macOS Recovery, Format the external SSD and Install macOS onto the external SSD. Then you can startup from the SSD and migrate your data from either the internal Fusion drive or your Time Machine backup during the initial setup.

Jul 17, 2019 8:27 AM in response to siddharth2604

You could also format the SSD and then clone your internal system to it using CarbonCopyCloner or SuperDuper; that way you would have the exact same thing.


And yes, you can erase the internal after you make sure that everything works as it is supposed to. You could then use it as a backup drive or extra storage. And the warranty will not be voided.

Install mac OS on external SSD

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