I want to ask you how can I get back together my Fusion Drive (merge HDD and SSD together). I was installing Windows 10 and during installation it crashed and I was not able to boot in Windows neither OS X. I also lost recovery partition, so I am going to install it with internet recovery or with my installed OS X on my external HDD. Thanks for any advice
- Detach any external drive (especially your external Time Machine backup drive)
Restart to Internet Recovery Mode by pressing alt cmd R at startup.
The prerequisites are the latest firmware update installed, either ethernet or WLAN (WPA/WPA2) and a router with DHCP activated.
On a 50 Mbps-line it takes about 4 min (presenting a small animated globe) to boot into a recovery netboot image which usually is loaded from an apple/akamai server.
I recommend ethernet because it's more reliable. If you are restricted to WIFI and the boot process fails, just restart your Mac until you succeed booting.
Alternatively you may start from a bootable installer thumb drive (preferably Yosemite or El Capitan) or a thumb drive containing a full system (preferably Yosemite or El Capitan).
Rebuild Fusion Drive
All data on the disks will be deleted.
- Booted to Internet Recovery Mode open Utilities → Terminal in the menubar and enter:
diskutil cs listto get a CoreStorage listing.
- Copy the Logical Volume UUIDs one by one, if any are listed.
- Now delete all Logical Volumes with
diskutil cs deleteVolume LVUUID.
- Copy the Logical Volume Group UUID, if any is listed. It's the first listed in the listing of
diskutil cs list.
- Then delete the Logical Volume Group with
diskutil cs delete LVGUUID.
exitand quit Terminal
- Open Disk Utility. Enter 'Ignore' if you are asked to fix the drives.
Choose your SSD and erase it: 1 Partition Mac OS X Extended (Journaled), GUID Partiton table and hit Erase.
Please check that the size is ~121 GB
Choose your HDD and erase it: 1 Partition Mac OS X Extended (Journaled), GUID Partiton table and hit Erase.
Please check that the size is ~2 TB
Quit Disk Utility and open Terminal
Example (your disk identifiers and sizes are different of course: Your volume SSD probably has the Identifier disk0s2 and the size 121 GB and your volume HDD probably has the Identifier disk1s2 and the size 2.0 TB):
diskutil cs create "Name" IdentifierSSD IdentifierHDD
In your case probably
diskutil cs create "Macintosh HD" disk0s2 disk1s2.
Copy the resulting LVGUUID
diskutil cs CreateVolume LVGUUID jhfs+ "Macintosh HD" 100%.
diskutil cs list
Check the size of your Logical Volume. It should have the size ~1.121 TB
- Open Disk Utility and check your newly created volume for errors
- Quit Disk Utility
- Open Restore OS X. Install and configure OS X. The original OS X your Mac came with will be installed.
- After configuring OS X, download the newest available system installer with App Store and upgrade your system.