Lost my SSD macintosh HD on my fusion drive, help!

Question

I have a 2015 iMac, 27 inch just released (oct 2015) which has a 3TB fusion drive. It came with El capitan installed on the iMac on delivery, to the SSD.I partitioned the drive twice, once with another OSX journaled partition, and another for windows bootcamp.Everything was working fine until today, the iMac would not boot to OSX. Boot camp did boot to windows fine, but El Capital would get stuck with after the apple logo, and before the login screen. it would stay a dark screen with a flickering curser in the top left hand corner every 10 seconds or so. I decided that i needed to re-install OSX. it installed right over the top, but I had the same issue on reboot. Even in safe mode it would still get stuck at the same point, and with the blocking curser every 10 seconds or so. With another re-install off a flash drive with el capital, in the disk utility it showed my three partitions, macintosh HD, second OS X partition, and bootcamp, all under fusion drive - all as expected. I clicked on the macintosh HD, and thought that it would need repair, what happened next was an error of some sort (cannot remember exactly), and then it completely disappeared.. and i have no idea how to get it back. I ended up installing onto the second OS X partition, and it all went well and booted fine. But now i only have two drives instead of three, and as far as i know I&#x27;m no longer using the SSD part of the fusion drive. I&#x27;m guessing that the main reason my machine didn&#x27;t boot today was because the SSD died? but the rest is fine, hence why i can boot from the second partition i made. Feel a bit ripped off, as i want to use the fusion if possible, or at least get it back as listed. &#x27;About this mac&#x27; lists my mac with a 3.12 TB Fusion drive.I&#x27;m not great with all of this, here is what &#x27;distil cs list&#x27; gave me:diskutil cs listCoreStorage logical volume groups (1 found)|+-- Logical Volume Group 4177C642-12ED-41D2-B725-6C1EE85D142F    &#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;&#x3D;    Name:         Macintosh HD    Status:       Online    Size:         1710271823872 B (1.7 TB)    Free Space:   1704416567296 B (1.7 TB)    |    +-&lt; Physical Volume AF4F097C-6845-4442-8E82-A07005092703    |   ----------------------------------------------------    |   Index:    0    |   Disk:     disk1s2    |   Status:   Online    |   Size:     120988852224 B (121.0 GB)    |    +-&lt; Physical Volume EBD4DF80-F840-45E6-AD2D-6E833E299C6B        ----------------------------------------------------        Index:    1        Disk:     disk0s2        Status:   Online        Size:     1589282971648 B (1.6 TB)It&#x27;s clearly missing over a TB of storage, which was my old macintosh HD thats now missing.How on earth do i get it back?Any advice would be appreciated.

poikkeus1 · Answer

it&#x27;s credible that the SSD part of the hybrid drive died, but you&#x27;re going to need an expert diagnosis on this. If you purchased the machine through Apple, it&#x27;s still under warranty, so at least you&#x27;re going to get the drive repaired. Frankly, I don&#x27;t know how you&#x27;re going to get the lost data back, though I assume you&#x27;re performing regular backups. At least, you&#x27;ll be able to get that data back.

pjbzqvp · Answer

I have already lost all the data, as El capital initially installed over the top and from what i saw before it disappeared, it actually formatted the disk also.I don&#x27;t care about the data, as i&#x27;ve only been using it for a while, I care more about getting the drive working again. You might be right, the only way to fix this is through taking the machine to apple to be fixed under warranty.

babowa · Answer

I believe (could be wrong) that El Capitan only allows 2 partitions, so you tried to create three which could explain the disappearance of your Macintosh HD - system install partition.Unless you have a bootable clone you can boot from or use internet recovery (Command + Option + R) to access Disk Utility and erase the entire drive and then reinstall the OS which might be the only option to get this to start over, I&#x27;d suggest taking it to your nearest Genius Bar (or call tech support). I&#x27;d try the clone or recovery option first. Also be aware that you have far less control over a fusion drive than a regular one and, only do two partitions (Macintosh HD and Windows).

pjbzqvp · Answer

Update and solve: I contacted Apple support and spoke with a technician. The issue came from my initial install and partition becoming corrupt somehow. I rebooted using apple internet restart (holding command-r) and from there he instructed me to use terminal and type in commands to entirely wipe the drive and all partitions. This was not something the disk utility could do. It had to be terminal commands.This cleaned all the previous partitions and resolved the issue, i was then able to re-install OS X el capital just fine, however i lost all data from all partitions.

kokopellie · Answer

I had the same problem and fought it for a week! It would not boot, just got a curser...This fixed mine:Restart your machine while holding the "SHIFT" key until you see a progress bar (Safe Mode). A window will open asking which user do you want to use. Select and enter your password. The screen may act strange, don&#x27;t worry. Go to PREFERENCE&#x27;s /USERS &amp; GROUPS/LOGIN OPTIONS. Turn on AUTOMATIC LOGIN and select your account &amp; enter password. Reboot and life will once again be GOOD! It seemed to be a thing with OS 10.11.1Man I hope this helps some of you.