How to Use Terminal to Split a Mac’s Fusion Drive
The Fusion drive on a Mac is made up of two physical drives: an SSD and a standard platter-based drive. A Fusion drive combines the best of both worlds; the wonderfully fast performance of the SSD and the delightfully large, and relatively cheap, storage space of a standard hard drive.
While the Fusion setup creates a nice performance boost for most Mac users, there may be a time when you no longer want the Fusion drive and would prefer to have two distinctly separate drives for your Mac. You may find that having separate drives is a better configuration for your data needs, or perhaps you just want to replace either the SSD or the hard drive with a larger or faster one. No matter the reason for doing it, separating the drives into their individual components is an easier task than Apple lets on.
Disk Utility Doesn’t Come to the Rescue
Disk Utility doesn’t completely support Apple’s Core Storage technology, which is the system behind the scene that allows the Fusion drive to work. Yes, you can see your Fusion drive in Disk Utility, and you can erase its data, but Disk Utility lacks a way to split the Fusion drive into its basic components. Likewise, there is no way to create a Fusion drive in Disk Utility; instead, you have to resort to Terminal to set up a Fusion drive.
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