Setting up Fusion Disk on an older Mac

Posted on November 02, 2012

Fusion Drive is the marketing name for a useful application of Core Storage. Core Storage is a Logical Volume Manager for OS X. Although it comes pre-configured on some newer Macs, it's possible to set up on an older Mac as well.

Warnings:

To begin, install your physical drives in your Mac. For me, I’m using the 250GB SSD that came with my Early 2011 MacBook Pro 17” along with a 1TB hard disk in the optical bay. In theory, you could use several drives in a Mac Pro. According to an AnandTech article, Apple’s solution only uses 128GB of flash, so this should be plenty sufficient, if not more performant.

Once you’re all built physically, reboot your machine, booting from your Time Machine hard drive. Open a terminal from the Utilities menu. Following Patrick Stein's examples, create your logical volume. Type diskutil list to find the identifiers for your disks. I'll repeat myself: This will destroy all data on the disks you specify.

After running the diskutil cs create and diskutil cs createVolume commands, close the terminal. Your volume has been created. Now, lets get your data back.

For me, restoring from my backup didn’t work for one reason or another (related to nuking the recovery partition). No matter. Select to reinstall OS X. After setup is complete, use Migration Assistant to restore your backup. This isn’t quite like a Time Machine restore, but close enough for my liking.

There is no next step. Enjoy!