Mac Mini automatically Raid/Fusioned my Drives ...

[Previse]

Alright well here's the story;

I wanted to bootcamp windows 8.1 on my L2012 Mac Mini Server edition. I've got 1 250gb Samsung Evo drive and 1 Tb that came with the mini. I made a partition and went to boot into bootcamp installer and windows stated "windows cannot install to this partition due to an error"

Restart into recovery mode, click disk utility; both drives RED colored, i click the top drive ( evo samsung) click verify disk and BLAM! Says 1.25Tb on "internal drive" 1 partition "macintosh HD" which is 1tb. THATS ALL.

Any suggestions? I'm stumped and have a brick for a mac mini currently....

Once i delete the volume group via diskutil both drives are RED and i cannot click anything once i do it says "fix" and automatically makes a group again ..

Thanks

 

[Mr. Retrofire]

Is this a beta version of OS X 10.9.2?

I ask this, because Apples CoreStorage framework recognizes only “Apple SSDs”, not for example Samsung EVO SSDs. It's possible that a newer version of OS X recognizes additional SSDs (not only “Apple SSDs”) and “thinks” you want a fusion drive.

 

[Previse]

Is this a beta version of OS X 10.9.2?

I ask this, because Apples CoreStorage framework recognizes only “Apple SSDs”, not for example Samsung EVO SSDs. It's possible that a newer version of OS X recognizes additional SSDs (not only “Apple SSDs”) and “thinks” you want a fusion drive.

10.9.1 (It was ...) And my recovery (Boot CMD+R) goes to ML recovery so i'm recovering ML then going to download a fresh Mavs and put on a USB drive and redo my new fusion setup to mavs.. I hate having a fusion drive, i'd prefer my drives be separated. I've tried deleting CS groups and nothing.

Also when i diskutil cs list i see about 14 disks ... wtf is going on?! Is there anyway to just wipe EVERYTHING and start fresh?

 

[Fishrrman]

[[ Restart into recovery mode, click disk utility; both drives RED colored, i click the top drive ( evo samsung) click verify disk and BLAM! Says 1.25Tb on "internal drive" 1 partition "macintosh HD" which is 1tb. THATS ALL. ]]

That's not a bug, it'a a feature....

Disk Utility has been deliberately set up by Apple to perform this way. That is, if you have both an SSD and HDD present that are not "already fused", when you launch Disk Utility, it will "see" the two (un-fused) drives as "damaged", and to repair them, it will automatically "fuse them together".

The user has no option to disable this process.
Why they set it up this way, I have no idea.

How to work around it:
I think what you need to do is to use Terminal to again "unfuse" the drives.
Then, still using Terminal, partition BOTH of the drives individually.
The drives are now "partitioned and prepped" and you DON'T have to launch Disk Utility to "touch them".
Remember, if you DO open Disk Utility, it may automatically attempt a "re-fuse".

At this point, install an OS onto one of the SSD partitions (I suggest the "first" one, with the lower ID number).

Once the OS has been installed, boot from it, create an account.
Now, download CarbonCopyCloner.
Next, CLONE the freshly-installed copy of the OS to the first partition on the HDD drive.

What you will end up with is a bootable OS on the FIRST partition of EACH drive.

Now I believe you can launch Disk Utility without it trying to "re-fuse" the two drives.

If there is a better workaround, perhaps others in the forum will jump in and post as to how they did it...

 

[tagy]

I just added a 250gb SSD to a 2012 mac mini, when I started disk utility from a usb stick both drives were red, but it gave me the option to 'fix' the fusion drive or skip.

I skipped this and formatted both drives and installed the OS on the SSD as normal.

 

[Fishrrman]

[[ I just added a 250gb SSD to a 2012 mac mini, when I started disk utility from a usb stick both drives were red, but it gave me the option to 'fix' the fusion drive or skip.
I skipped this and formatted both drives and installed the OS on the SSD as normal. ]]

I'm going to _guess_ that the reason you got the "option to option out" of fusion was because you were booted up from a completely _external_ source -- in your case, a USB flash drive.

I believe the OP was trying to "boot internally" -- from the recovery partition _inside_ the Mini (with no external drives connected).

In that case, the "option out" option may not appear -- in other words, Disk Utility goes right ahead and "re-fuses" the drives, whether you want that to happen or not.

I don't have a Mac with an SSD and HDD inside (I boot and run my Mac Mini from an SSD mounted _externally_ in a USB3/SATA dock). So I haven't actually seen what happens -- my thoughts above are what I've gathered from other reports around the net...