Cannot erase/partition Fusion drive

Hi everyone,
When I got my iMac, with a 1TB Fusion drive, I partitioned it, with a small partition running OS X and apps, and another larger one, to contain my user files - photos, documents and so on.
Now I want to sell my iMac, and I want to re-partition my Fusion drive, to only one partition, like when I bought it. But it cannot be done. Se screenshot bellow. Everything is greyed out.
I have tried to boot into reinstall mode, via CMD-R, with no luck.
I have tried running OS X from another USB drive, no luck.
And the one partition listed in the screenshot, won't mount. Have I messed up completely?
Best regards
Soeren Vedel

Boot into your Recovery HD using Internet Recovery (Command+Option+R). You should see a spinning globe and it should take a few minutes to get to the OS X Utilities menu. This boots into Apple's server.
Open Terminal and type: diskutil cs list
Copy the Logical Volume Group UUID which is a string of letters/numbers/dashes. This should be the 1st line after the above command.
Type: diskutil cs delete <LVG UUID from the previous step> (without the brackets)
After the delete completes open Disk Utility and you may see your two drive (SSD, HDD) in RED. You will be prompted to IGNORE or FIX. Choose FIX to recreate your Fusion Drive.
Close DU and select Reinstall OS X from the menu list. After the reinstall completes Shutdown. Your Mac is now setup to factory OS.

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Hi,
I bought an iMac Retina 5K in Dec. 2014. I am using OS X 10.10.1, 3T fusion drive. Now I want to erase and re-install OS X. However, when I enter the recovery mode, the os does not let me erase the partition. After first attempt of erase, all the selection and button became gray and un-selectable.
I want do know if it is normal that I cannot erase for the new model. How can I erase and re-install, or restore to factory state.
Thank you so much!

I just returned a new iMac with a fusion drive after one week (many power related problems) - I also had a problem erasing, but finally managed by choosing the actual drive, not the top most entry in the Disk Utility window. I no longer have it now to do a screenshot, but I am referring to the actual hard drive like this one:
As to not being able to choose the top entry - I believe this is the behavior because of the fusion drive/SSD which you have no control over.

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See iMac (27-inch, Late 2012): Boot Camp alert with 3TB hard drive

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Background
I tried reformatting while running Snow Leopard, but the option was grayed out and the install disc made the computer hang at the white bootup screen. I figured I'd just upgrade to Lion and do a clean install (not an option).
Problem
After upgrading to Lion, I booted into recovery to erase the hard drive. I did it and it took less than ten seconds (bad sign).
Now I can't get past recovery and the hard drive is still full.
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In Disk Utility I have following options:
500.11 GB Hitachi HTS5....
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disk1
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Repairing the "Untitled" disk originally gave me an error ( Error 16: resource busy I believe). I received a similar error when I tried to unmount it (Error 256 I believe).
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Now after restarting a few times, it "repairs" just fine and I can mount and unmount it just fine. When I try to install Mac OS X, however, it'll give me an estimated completion time of 156 hours and 2 minutes, disappear, then start me over on the installation screen. If try again it again, it just hangs on the download screen without even offering an estimated completion time.
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Help, please?

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Hello,
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1: If near a Apple Store or Authorized Repair, take it to then for a free evaluation, it might have other hardware problems now that it would be a waste of effort even continuing.
2: The RAM needs to be
Maximum Memory
3.0 GB (Actual) 2.0 GB (Apple)
Memory Slots
2 - 200-pin PC2-5300 (667MHz) DDR2 SO-DIMM
Basically what this means is you can put in a 2GB module and a 1GB module for 3GB total.
I wouldn't proceed with installing RAM just yet, not until you get a stable OS X version on the machine, you might have a hard drive needing to be replaced as well which you can do while inserting new RAM.
3: This User Tip can assist in installing 10.6 Snow Leopard, partition format etc.
How to erase and install Snow Leopard 10.6
Software Update fully immediately after setup.
There is no need to install Tiger, he 10.6 disk contains the full 10.6 version, you can either install the iLife from Tiger disks or use Pacifist from Charlesoft to extract them and place on your new install, then Software update to get them current.
4: If not successful then the drive also likely needs to be replaced, if so choose a 7,200 RPM SATA I w/1.5Gb/s connection.
Install/upgrade RAM or storage drive in Mac's
Repeat #3
If your getting beeping noises or "you need to restart" issues, it's likely one or more of the RAM modules is bad. Have it exchanged or swapped.
I advise good quality RAM the first time, if you buy cheap stuff it's just going back.
Don't go any further than 10.6.8 with that old machine, the performance will be terrible.

Erase partition on drive

Hi all.
I am using disk utility version Version 13 in mavericks 10.9.2 - and just partitioned a new Seagate 4TB SSHD drive into 2 x 2TB partitions.
(by the way... disk utility only gave me an option to split 4TB into 2 x 2TB partitions. No functionality to choose the size you want, I did want 1 x 3TB and 1 x 1TB partitions).
Now I want to revert back to a single 4TB drive but everything is greyed out in disk utility and my drive only appears at 2 partitions.
I tried erasing them but they still only show as partitions.
I can't see any way to revert back to my 4TB single drive.
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Mike

Hello
Thanks for coming back to me.
Regarding the initial partition resizing via "moving the top or bottom of the rectangle to increase it or decrease it" - this functionality was greyed out and you could not move anything. It had pre selected 2 x 2TB and would not let me enter a new figure numerically or pull the slider rectangle boxes around.
In this picture you see my partitioned drive highlighted in blue in the side bar.
As you see it's split into 2 drives
AUDIO & SOUNDS - HD MIRROR 4TB
and
AUDIO & SOUNDS - HD MIRROR 4TB 2
In the main window you see that when I go to the partition tab on either drive everything is greyed out.
I don't see a "Partition Scheme dropdown menu"
Any ideas?
Thanks so much.
Mike

Newly installed firefox has left an blue "drive" icon on my (Mac) desktop that I cannot erase. When I click on firefox in applications, it always brings this up and won't start firefox directly. I cannot erase this "firefox" drive icon, it won't let me. E

The icon is blue with a white firefox logo on it. My only options are to "Burn 'Firefox'" or "Eject 'Firefox'" when I click on it to edit it, but I cannot cut, paste, or move to trash. It won't let me. When I click on "Eject 'firefox'" it says "The disc firefox is in use and could not be ejected". Even when I am running no applications whatsoever.
When I click on this icon, a small window appears with two icons in it: one the firefox browser icon, and the other the applications folder icon with an arrow inbetween the two. When I drag the icon into the application folder it tells me:
"An item named 'firefox' already exists in this location. Do you want to replace it with the one you're moving?"
And no matter how many times I "replace it" the icon never goes away.
And no matter how many times I replace it, whenever I click on the firefox icon in applications, it brings up this tiny window on my desktop before it will actually start running the firefox web-browser. And it will never reload my previously saved tabs is also my main concern.
== This happened ==
Every time Firefox opened
== a few weeks ago since I installed...

Maybe you copied the icon show in the window to your application and into your dock directly. Try closing your Firefox again. Eject the disc again. Then go to your application folder. You should see Firefox with a circle and cross through it. Open it. It should open without the blue icon appearing on your desktop again.

Larger Flash in the Fusion drive

I want a new iMac for music composition and would like a 1 or 3GB fusion drive with the flash portion of 512GB. Is this possible and if not, can I have two SSDs fitted?

iMacs only come with a single internal drive. A second drive cannot be installed; there's no room. Apple's Fusion drive comes 1TB or 3TB with a 128GB SSD integrated. You cannot order a Fusion drive with a larger SSD partition. You can only order a single SSD-only internal drive up to 1TB. That's it.
iMacs come with 2 Thunderbolt ports and 4 USB3 ports that can support expremely fast external drives, as many as you want, any size you want.

My Fusion Drive was splited in two

Hi to everyone.
I bought a mac mini late 2014 with fusion drive last month. My brother did the initial configuration with his apple id. When I tried to change to my apple id I didn`t get it. Then, I use ˜Find my Mac~to erase the mac mini and start over. But, when I tried to install OS X again the Fusion drive appeared splited in two: 120GB of SSD and 1TB of SATA HDD. I did the installation but now, I have two drive units in mac.
How can I join/merge these partitions? Am I need to reinstall OS X?
Thanks

Allan Eckert wrote:
There are command line instructions to create a Fusion Drive available on the web.
No need for any command lines.
Before doing any of below steps, if there is anything on the Mac Mini that needs to be saved, make sure that you have a valid backup of it: Mac Basics: Time Machine backs up your Mac - Apple Support
Start your mac and boot to Internet Recovery - power ON Mac Mini and after releasing power button (before mac's chime) press and hold ALT+CMD+R: let go buttons when you see spinning globe or - if you are using WiFi connection - when on the screen appears prompt to select WiFi network.
OS X: About OS X Recovery - Apple Support
When Interent Recovery is loaded, after prompt with choosing prefered language, select Disk Utility app and choose continue.
Next, select on the Disk Utility sidbar one of the disks that should be combined as Fusion Drive: Disk Utility will recognized that there is a problem with Fusion Drive and will prompt with question if you want to fix it. Selecting "FIX" button will re-create Fusion Drive and most likely erase all data on both drives.
More info: Mac mini (Late 2012 and later), iMac (Late 2012 and later): About Fusion Drive - Apple Support - check section "Lern More - Troubleshooting".
EDIT:
Learn more
Troubleshooting
The version of Disk Utility that comes with Fusion Drive is unique. Earlier versions of Disk Utility can't be used with a Fusion Drive.
If your system will not start because you see a flashing question mark or another alert:
Press the Power button and hold it down to power off your system.
Press the Power button again. After you hear the startup chime, press and hold Command-Option-R to start up to the Internet version of OS X Recovery.
A globe should appear with a "Starting Internet Recovery" message. It is now OK to release Command-Option-R.
A progress bar should appear and Internet Recovery should start and ask you to select a language.
Once you select a language, click Disk Utility in the window that appears and then click Continue.
If your Fusion Drive can be fixed with Disk Utility, you'll see a Disk icon with red lettering. Click the disk icon.
A dialog box appears offering to fix the Fusion Drive (shown above). Caution: Clicking Fix will erase your Fusion Drive. If you have a Time Machine backup of your Fusion Drive Mac, see Mac 101: Time Machine for information on how to restore from a Time Machine backup once the drive has been erased.
After the process is complete, the volume will change color to black. Quit Disk Utility, click Install OS X, then click Continue.

Erasing G4 hard drive?

I have an old IMac G4 flatscreen, the one with the round base, that I want to ditch. But I cannot erase the hard drive through the usual methods. I have long forgotten the password, so I can't log on. The startup disc takes me to the logon screen and I can't continue. Now I think my only option is to remove the hard disc and crush it in a vice and take everything to the recycling center in pieces. Any advice?

No, don't do that...
If it's running a release of Mac OS X, do you have the installation disc? Actually, it can be any disc that installs Mac OS X, that will boot that iMac.
Insert the Mac OS X installation disc and start up with the C key held down, to boot from the optical drive. When it gets to the first Installer screen, from the menu bar select to run Disk Utility. Depending on Mac OS X version, this will either be under Installer or Utilities.
In Disk Utility, you are securely erasing the internal drive (the entire drive). Select the internal drive in the sidebar, not the volume indented under the drive. Click on the Erase tab. Select Mac OS Extended (Journaled) as the Format. Name it Macintosh HD. Click on Security Options (or Options). Select the option to Zero Out Data. This option writes zeros over the entire drive and makes your data essentially unrecoverable (except maybe to VERY sophisticated equipment and specialists). This will take a lot longer than a regular erase.
When it finishes, quit Disk Utility to go back to Installer, and run the Mac OS X installation. (Actually, you don't have to run the installation if your goal is only to erase the hard drive. But it be may be a good idea to make it bootable, if you there might be a new owner.)

How to reset 3TB fusion drive to original partition scheme

When I first purchased my 27" iMac in early 2013 I was unable to use Boot Camp to create a Windows partition (with the version of OSX it shipped with bootcamp was initially disabled but added in an update later). I found a guide online for untangling the Fusion Drive partitions and essentially setting up bootcamp manually.
However, a few days ago I had Windows 8 get screwed up and needed to reformat. I figured that since Apple now updated Mavericks to allow my machine to use bootcamp I would start from scratch and do it properly. The problem is, I cannot seem to get my machine back into a "factory default" setup. I tried removing the CoreStorage volume and letting the Disk Utility tool "reset" the drive, and that -seemed- to work. I had one 3TB partition (according to the GUI) and re-installed OSX. I used Bootcamp to split 2TB for Windows (games) and leave 1TB for Mac. Everything went fine and I restarted into the Win8 installer. However, at this point Windows refused to install to the 2TB partition. I tried formatting it, and delete/create but it said it couldn't install to that partition. The confusing part is that according to Windows I had about 8 partitions (EFI and Recovery I understand but the rest I don't know the reason for).
So now I'm back at the OSX Recovery and this is what "diskutil list" is giving me. Why are there all these 524.3 KB partitions? I can't seem to remove or merge them. I know I should have recorded what the original structure is, but it's too late now. Can someone tell me what the 3TB Fusion Drive *should* look like, and how I can get back to that?
bash-3.2# diskutil list
/dev/disk0
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *121.3 GB   disk0
   1:                        EFI EFI                     209.7 MB   disk0s1
   2:          Apple_CoreStorage                         121.0 GB   disk0s2
   3:                 Apple_Boot Boot OS X               134.2 MB   disk0s3
/dev/disk1
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *3.0 TB     disk1
   1:                        EFI EFI                     209.7 MB   disk1s1
   2:          Apple_CoreStorage                         144.2 GB   disk1s2
   3:                 Apple_Boot Boot OS X               650.0 MB   disk1s3
   4:       Microsoft Basic Data                         2.1 TB     disk1s4
   5:          Apple_CoreStorage                         801.4 GB   disk1s5
   6:                 Apple_Boot Boot OS X               134.2 MB   disk1s6
/dev/disk2
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:     Apple_partition_scheme                        *1.3 GB     disk2
   1:        Apple_partition_map                         30.7 KB    disk2s1
   2:                  Apple_HFS OS X Base System        1.3 GB     disk2s2
/dev/disk3
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:                  Apple_HFS Macintosh HD           *1.1 TB     disk3
/dev/disk4
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:                            untitled               *524.3 KB   disk4
/dev/disk5
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:                            untitled               *524.3 KB   disk5
/dev/disk6
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:                            untitled               *524.3 KB   disk6
/dev/disk7
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:                            untitled               *524.3 KB   disk7
/dev/disk8
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:                            untitled               *524.3 KB   disk8
/dev/disk9
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:                            untitled               *6.3 MB     disk9
/dev/disk10
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:                            untitled               *2.1 MB     disk10
/dev/disk11
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:                            untitled               *1.0 MB     disk11
/dev/disk12
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:                            untitled               *524.3 KB   disk12
/dev/disk13
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:                            untitled               *524.3 KB   disk13
/dev/disk14
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:                            untitled               *1.0 MB     disk14
Also including what my CoreStorage structure looks like...

Since it won't let me edit my post, here is the text from the picture:
CoreStorage logical volume groups (1 found)
|
+-- Logical Volume Group CB783377-EA29-4751-B149-FE6B210648B5
    =========================================================
    Name:         Internal Drive
    Status:       Online
    Size:         1066587906048 B (1.1 TB)
    Free Space:   12288 B (12.3 KB)
    |
    +-< Physical Volume 0221F6E1-8EE1-453A-A0EB-B32348EB6E53
    |   ----------------------------------------------------
    |   Index:    0
    |   Disk:     disk1s2
    |   Status:   Online
    |   Size:     144162512896 B (144.2 GB)
    |
    +-< Physical Volume F74A0E21-6435-4CB2-801F-95682108A391
    |   ----------------------------------------------------
    |   Index:    1
    |   Disk:     disk0s2
    |   Status:   Online
    |   Size:     120988852224 B (121.0 GB)
    |
    +-< Physical Volume C2BD0D1A-7EA2-4E36-A3EF-82A7E63BE439
    |   ----------------------------------------------------
    |   Index:    2
    |   Disk:     disk1s5
    |   Status:   Online
    |   Size:     801436540928 B (801.4 GB)
    |
    +-> Logical Volume Family 9DD06D63-96CD-4088-8F0E-061026E68C29
        Encryption Status:       Unlocked
        Encryption Type:         None
        Conversion Status:       NoConversion
        Conversion Direction:    -none-
        Has Encrypted Extents:   No
        Fully Secure:            No
        Passphrase Required:     No
        |
        +-> Logical Volume A531CC02-E337-473E-8F1F-F462595E1354
            Disk:                  disk3
            Status:                Online
            Size (Total):          1060804022272 B (1.1 TB)
            Conversion Progress:   -none-
            Revertible:            No
            LV Name:               Macintosh HD
            Volume Name:           Macintosh HD
            Content Hint:          Apple_HFS

HT4818 When I try to partition my hard drive for Windows 7, I get an error saying The disk cannot be partitioned because some files cannot be moved. I have a 2006 Macbook Pro I believe and I really need assistance as soon as possible.

I have Windows 7 Premium Home and I have downloaded the Drivers and when I click Boot Camp Assistance to partition my hard drive, it says, "The disk cannot be partitioned because some files cannot be moved. Back up the disk and use Disk Utility to format it as a single Mac OS Extended (Journaled) volume. Restore your information to the disk and try using Boot Camp Assistant again." I can't do any backup really because I don't have an external hard drive to work with. I tried repairing disk permissions but that did not do anything. I really need a lot of help with this with some easy, step-by-step tutorials or something. I believe I have a 2006 version of Macbook Pro(4,1).

Once you have obtained an external drive and connected it you will 'clone' your internal drive to it.
Download Carbon Copy Cloner (it is not free but there is a fully functional trial version which is). Use it to clone your internal drive to your external drive. When that is done you will reboot from the clone and use Disk Utility to erase the internal drive (choose Mac OS Extended (Journaled)) as the format (this is normally preset, but check). Make sure to give the external drive a 'distinctive' name, don't want to get drives mixed up in this process.
Once that is done you will use Carbon Copy Cloner (from the clone) to restore the external to the internal.

BootCamp cannot create new partition on drive free space.

Hi Folks,
I am hoping for some advice here. I am running OS X (10.5.6) and wish to use Boot Camp to created a partition to install Windows XP SP2 for some gaming. My machine is a late 2007 MBP 2.4GHz C2D, 4GB RAM, 340GB WD transplanted hard drive.
I have about 180GB of free space for a new partition to be created for the XP install.
When I fire up the Boot Camp Assistant tool, I am immediately informed of the following:
"The startup disk cannot be partitioned or restored to a single partition."
"Back up the disk and use the Disk Utility to format it as a single Mac OS Extended (Journaled) volume. Restore your information to the disk and try using the Boot Camp Assistant again."
+ I have never had more than one partition on this drive.
+ I installed the drive new with no partition and used a tool named 'Carbon Copy Cloner' to transfer data from the original drive onto this drive, the machine booted right away and I have been using it without issue ever since.
+ I have run Disk Utility to 'Verify Disk', 'Verify Disk Permissions' and 'Repair Disk Permissions' all ran with no problems and completed successfully.
My question is, how can I make a usable backup copy of the drive to restore back to the drive after performing the re-format?
Can I use the Carbon Copy Cloner software for this? I want to make sure that the resulting internal drive is bootable, etc.
I have been running Time Machine as well and have a disk full of backups from that app, but I have no idea how to use it to restore the drive to it's current state after re-partition and format.
Thanks in advance for any and all suggestions.
John

So today I used the free "trial" version of SuperDuper to create a bootable clone of my primary internal drive.
It was about 100GB and took a long time to copy onto USB 2.0 external SATA drive, but it worked.
SuperDuper provided the option to make the copy the boot device as well. After reboot, I used OS X Disk Utility to erase primary drive.
I then performed the operation in reverse, copying the entire contents back to the original location.
After a reboot, I ran the Boot Camp Utility and received the same aggravating message which I received before.
How can I be sure that I am actually re-formatting the target drive in order to consolidate free space? Is this my issue? When I performed the erase operation, I skipped the "zero out free space" step. Am I using the correct utility to prepare the target drive?
Once again, any and all help is greatly appreciated.
Regards,
John

After attempting secure erase, iMac w/homemade fusion drive won't boot from *anything*

2009 iMac with homemade fusion drive (SSD installed in optical bay). Was working fine with Yosemite until I attempted to secure erase it before giving away the machine.
Now the drive is borked. Disk utility could make no sense of it, can't reformat, it can't repartition it. And now it has completely stopped booting. I cannot even get it to boot of an external USB drive anymore (the original operation was performed while booted from a Yosemite installer drive on a USB stick).
I've reset the PRAM, reset the SMC, and just nothing. All boots are attempted from internal messed up fusion drive, which eventually ends in the "prohibitory sign".
I'm not even sure what to try at this point. Any suggestions out there?

Thank you for the reply. I have since resolved the problem, although not in the most satisfactory way.
Here's what I did:
Pulled both drives out of the iMac, put them into a USB dock, and reformatted each one. Both drives appeared at this point to be fine.
Reinstalled both drive into the iMac, and started up from a USB drive. No problem.
Recreated the fusion drive from the terminal. No problem.
Now, because I am a glutton for punishment, I tried wiping the fusion drive again. This time, part way in, it kernel panicked. Luckily, I was able to reboot once again to the external drive.
At this point, the fusion drive was in the exact same messed up state as when I started. Disk Utility app could do nothing with it.
Fortunately, this time I went right to the command line, and was able to fix things up and recreate the fusion drive before anything else bad happened.
I gave up on wiping the drive for now. If I need to do so in the future, I will disable the fusion drive and try to wipe each physical drive separately.
I should note that this iMac has never given a spot of trouble before now, so I am highly suspicious of the way disk utility tries to wipe a fusion drive. I certainly won't try it again. (I don't know if it has ever kernel-panicked before in the 5 years I've owned it).

Cannot erase/partition Fusion drive

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