Creating a Fusion drive on a late 2012 Mac Mini

[Ubele]

I thought that this would be a no-brainer, but I'm finding conflicting information when I research. I have two late 2012 Mac minis that I want to upgrade with Fusion drives. The first is my wife's i5 with the stock 500GB HDD. I bought the OWC upgrade kit with a 120GB SSD, and I have a 1TB HDD that I'm going to use to replace the 500GB drive. It's one of those minis where the boot drive is in the upper bay. I bought the necessary add-on kit and have the OWC instructions for this configuration. I have an electrical engineering degree and have worked as a technician, so I'm fine with the physical part of the installation. I'll be migrating the data from another Mac mini, for which I also have a bootable clone HDD.

My confusion is with what I need to do to create the Fusion drive. I've found instructions from 2012, 2014, 2015, 2016, and 2017. They all reference Mountain Lion, giving the Terminal commands to create a Fusion drive, but saying that later versions of OS X should let you do it from Disk Utility. (Why would a 2017 post talk about Mountain Lion?) Then I read a couple threads saying that if you bought a Mac mini 2014, it came with a special version of OS X Disk Utility that lets you create a Fusion drive, but "regular" versions of OS X don't let you do this. Then I found a thread saying that the Terminal method doesn't work in Sierra. I found other threads saying that this is nonsense.

Can someone please tell me what I need to do from the software standpoint? I have a new SSD and HDD that I'll install in my wife's i5 Mac mini, and I want to create a Fusion drive. I'll migrate the data afterward from my other Mac mini (an i7 quad-core).

Then I want to do something similar with my i7 Mac mini. It has the stock 1TB HDD. I want to create a Fusion drive with a 1TB SSD and a 2TB SSD. The boot drive is in the lower bay in this computer. The only difference is that I also want to create a Boot Camp partition for Windows 10. I also have a 2015 13" MBP, and I'll either migrate the data from that or do a fresh install of everything, but the idea is that my 3TB Mac mini will be my "base station," and my MBP will be my mobile computer. I'm starting a business, and I figured it's a good idea to have two computers in case something happens to one of them.

Anyway, please point me in the right direction, and let me know of any caveats I need to be aware of. Thanks!

 

[chrfr]

They all reference Mountain Lion, giving the Terminal commands to create a Fusion drive, but saying that later versions of OS X should let you do it from Disk Utility.

With the 2012 Mac Mini you won't need to do anything with terminal to create the Fusion Drive. Because that computer natively supports the Fusion Drive, you'll be able to create it with Disk Utility. Remember that you will lose all data currently on the existing disk, so be sure to have a backup that you know works.

 

[Ubele]

With the 2012 Mac Mini you won't need to do anything with terminal to create the Fusion Drive. Because that computer natively supports the Fusion Drive, you'll be able to create it with Disk Utility. Remember that you will lose all data currently on the existing disk, so be sure to have a backup that you know works.

Thanks -- that's good to know!

 

[hallux]

Not even Disk Utility was needed in my case. When I installed an SSD in my 2012 Mini I was prompted for Fusion Drive creation during the OS install, since it detected the combo of SSD and platter drives.

 

[Fishrrman]

OP:

You might also consider just letting the two internal drives REMAIN "two internal drives".

If you do this, the SSD will always run at its best.

Once you get used to having two (or more) drives on the desktop, it's easy.

 

[Ebenezum]

OP:

While I agree with Fishrrman there is another thing to consider. Fusion Drive resembles RAID-0, if one of the drives fails its likely you can't recover much information. I have assisted friends with failed Fusion Drives and in all cases I was able to recover less information than from a single hard drive/ SSD.

I'm not saying you can't use it but you should definitely make sure to backup it regularly.

 

[Ubele]

Not even Disk Utility was needed in my case. When I installed an SSD in my 2012 Mini I was prompted for Fusion Drive creation during the OS install, since it detected the combo of SSD and platter drives.

That's good to know. I finished the physical installation in the i5 Mac mini on Sunday night. It wasn't as difficult as I'd feared. The OWC videos are very good, and I took my time, being careful not to break any of the connectors. The hard drive housing in the upper bay was different from what was shown in the videos, but it was easy enough to figure out. Now I hope it boots up and the formatting and data migration go well!
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OP:

You might also consider just letting the two internal drives REMAIN "two internal drives".

If you do this, the SSD will always run at its best.

Once you get used to having two (or more) drives on the desktop, it's easy.

Thanks for the suggestion. The i5 mini will be for my wife, and for her needs, I think the Fusion drive will be better. I bought an inexpensive 120GB SSD and paired it with a 1TB HDD I had from another computer. She's not technical, and she doesn't prune her email or her Photos collection, so the stock HDD is excruciatingly slow.

If all goes well, I'll upgrade my i7 quad-core mini. I've considered having two separate drives in that, rather than a Fusion drive, but I haven't decided for sure. That will be my "base station" computer, used for the usual email/web browsing/iTunes/Photos/MS Office/media storage, but also for a WordPress-based business site I've created. I use Adobe CC and various photo-editing programs to create content. It's mostly text and photography at this point, but I plan to branch into YouTube video and music production. In a couple years, I'd like to get a 5K iMac, but the i7 mini with two 1080P monitors has been fine for my current needs, except for the slow HDD.
[doublepost=1493074250][/doublepost]

OP:

While I agree with Fishrrman there is another thing to consider. Fusion Drive resembles RAID-0, if one of the drives fails its likely you can't recover much information. I have assisted friends with failed Fusion Drives and in all cases I was able to recover less information than from a single hard drive/ SSD.

I'm not saying you can't use it but you should definitely make sure to backup it regularly.

Thanks! Yes, I'm obsessive about making backups: daily Time Machine and Carbon Copy Cloner backups at home, and weekly TMB and CC backups that I store off-site, as well as what I store in iCloud and Dropbox. Hard drives have gotten so cheap.

 

[Ubele]

With the 2012 Mac Mini you won't need to do anything with terminal to create the Fusion Drive. Because that computer natively supports the Fusion Drive, you'll be able to create it with Disk Utility. Remember that you will lose all data currently on the existing disk, so be sure to have a backup that you know works.

Not even Disk Utility was needed in my case. When I installed an SSD in my 2012 Mini I was prompted for Fusion Drive creation during the OS install, since it detected the combo of SSD and platter drives.

Thanks, both of you. I booted my Mac mini from a USB 3.0 Sierra installer flash drive. Disk Utility detected the SSD, which I used to replace the original 500GB HDD, which was in the upper bay. It didn't detect the 1TB HDD I added to the lower bay, though. I know the drive is good, because I formatted it from another Mac before I installed it. Should Disk Utility have detected it immediately? If so, I'm guessing that the SATA cable isn't connected properly. I was very careful and didn't break anything. Are there any other possibilities to consider before I open the mini back up?

 

[hallux]

I would check the connections.

 

[chrfr]

Thanks, both of you. I booted my Mac mini from a USB 3.0 Sierra installer flash drive. Disk Utility detected the SSD, which I used to replace the original 500GB HDD, which was in the upper bay. It didn't detect the 1TB HDD I added to the lower bay, though. I know the drive is good, because I formatted it from another Mac before I installed it. Should Disk Utility have detected it immediately? If so, I'm guessing that the SATA cable isn't connected properly. I was very careful and didn't break anything. Are there any other possibilities to consider before I open the mini back up?

It's easy to have the connector from the SATA cable to the board look like it's connected but not actually be connected. Sometimes the process of putting it all back together will pop that cable off the connector.

 

[Ubele]

That was indeed the problem: the SATA connector for the HDD wasn't fully snapped into place.

I wasn't able to automatically create a Fusion drive, though: OS X (Sierra) Installer gave me a choice of either the SSD or the HDD. I chose the SSD, figuring Installer would automatically create a Fusion drive, but it installed Sierra on the SSD and kept the HDD separate. So I followed the instructions on how to use Terminal to create a Fusion drive, and all went well.

The i5 Mac mini feels like a brand-new computer! I'll do the same to the i7 mini. I know the installation will be easier the second time around. Thanks to all of you who offered help!

 

[chrfr]

I wasn't able to automatically create a Fusion drive, though: OS X (Sierra) Installer gave me a choice of either the SSD or the HDD. I chose the SSD, figuring Installer would automatically create a Fusion drive

You would have just needed to open Disk Utility and it would've offered to repair the Fusion Drive.

 

[Ubele]

You would have just needed to open Disk Utility and it would've offered to repair the Fusion Drive.

I did, but it didn't. It all ended well, though.