Reseting fusion drive iMac.

[alexdeepsoup]

I have a fusion drive on my iMac (HDD+SDD). Anyways I screwed it up by formatting my SSD while trying to bootcamp my imac. I reinstalled OS X on the SDD and started fresh. I used third party recovery tools, to recover what I needed from the HDD. Now I want to clear my entire computer and start fresh. Is there some magical "re-start button" that will re-create my fusion drive and format everything as it came in the box? Or will I have to do that my self with terminal and such? How do I fix this? What is the best way to go. Thanks a lot!!!!!


Also, If Im posting a forum in a wrong section, or if this has already been asked, I apologize. Just signed up today!! thx

 

[Weaselboy]

https://support.apple.com/en-us/HT202574

Follow the instructions at the very bottom of this page.

 

[tsang2320]

If the fusion drive is broken or split, disk utility will prompt upon launched.

 

[BLUEDOG314]

If you are having trouble letting disk utility fix things which I wouldn't be surprised on El Cap, you can always manually do it like this:

http://www.macworld.com/article/2014011/storage-drives/how-to-make-your-own-fusion-drive.html

The only thing you may have to do before all of this is manually destroy the existing remnants of the logical volume group on the HDD. Do this by typing in terminal "diskutil cs list" and if you have any existing logical volume groups copy their UUIDs and then type "diskutil cs delete LongUUIDGoesHere" then follow directions from link.

 

[oliverd]

Hi all,
i hope it is ok if i post here. iMac later 2012 fusion drive 1tb. diskutil cs list (no corestorage device found) ... fusion dissapred, (deleted partions/hdd scheme or what not using random instructions online not nesseserally knowing what i am doing :| now:
-only ssd as a storage flash avaliavable 123 GB ...i managed to install siera on it.

I am wondering if there is a way to find the missing part of 1TB or since it is not showing in diskutil list, is smiply dead now out of using/abusing dozens of terminal commands from creating and deleting cs...etc , zeroing, all things done in network recovery /endless restarting and waithing and trying for days now .... now I am booted using USB sierra install.

originally i wanted to delete all partitions, have a fresh hdd, because hdd acted slow, deliting partitions, veryfying permitions failed at some pont than i had to force restart...than trying so many thing just ended up with this:

@Weaselboy and others if possible to help? (I have no apple care, 4 years old machine, apple service in another farway town ...etc.. so online help is the only solution at the moment. greatful, Oliver.

-bash-3.2# diskutil list

/dev/disk0 (external, physical):

   #:                       TYPE NAME                    SIZE       IDENTIFIER

   0:     FDisk_partition_scheme                        *15.7 GB    disk0

   1:                  Apple_HFS Install macOS Sierra    15.7 GB    disk0s1


/dev/disk1 (disk image):

   #:                       TYPE NAME                    SIZE       IDENTIFIER

   0:      GUID_partition_scheme                        +5.8 GB     disk1

   1:                        EFI EFI                     209.7 MB   disk1s1

   2:                  Apple_HFS OS X Install ESD        5.5 GB     disk1s2


/dev/disk2 (disk image):

   #:                       TYPE NAME                    SIZE       IDENTIFIER

   0:      GUID_partition_scheme                        +2.1 GB     disk2

   1:                  Apple_HFS OS X Base System        2.0 GB     disk2s1


/dev/disk3 (disk image):

   #:                       TYPE NAME                    SIZE       IDENTIFIER

   0:                            untitled               +5.2 MB     disk3


/dev/disk4 (disk image):

   #:                       TYPE NAME                    SIZE       IDENTIFIER

   0:                            untitled               +524.3 KB   disk4


/dev/disk5 (disk image):

   #:                       TYPE NAME                    SIZE       IDENTIFIER

   0:                            untitled               +524.3 KB   disk5


/dev/disk6 (disk image):

   #:                       TYPE NAME                    SIZE       IDENTIFIER

   0:                            untitled               +524.3 KB   disk6


/dev/disk7 (disk image):

   #:                       TYPE NAME                    SIZE       IDENTIFIER

   0:                            untitled               +2.1 MB     disk7


/dev/disk8 (disk image):

   #:                       TYPE NAME                    SIZE       IDENTIFIER

   0:                            untitled               +524.3 KB   disk8


/dev/disk9 (disk image):

   #:                       TYPE NAME                    SIZE       IDENTIFIER

   0:                            untitled               +524.3 KB   disk9


/dev/disk10 (disk image):

   #:                       TYPE NAME                    SIZE       IDENTIFIER

   0:                            untitled               +6.3 MB     disk10


/dev/disk11 (disk image):

   #:                       TYPE NAME                    SIZE       IDENTIFIER

   0:                            untitled               +2.1 MB     disk11


/dev/disk12 (disk image):

   #:                       TYPE NAME                    SIZE       IDENTIFIER

   0:                            untitled               +1.0 MB     disk12


/dev/disk13 (disk image):

   #:                       TYPE NAME                    SIZE       IDENTIFIER

   0:                            untitled               +2.1 MB     disk13


/dev/disk14 (disk image):

   #:                       TYPE NAME                    SIZE       IDENTIFIER

   0:                            untitled               +524.3 KB   disk14


/dev/disk15 (disk image):

   #:                       TYPE NAME                    SIZE       IDENTIFIER

   0:                            untitled               +524.3 KB   disk15


/dev/disk16 (disk image):

   #:                       TYPE NAME                    SIZE       IDENTIFIER

   0:                            untitled               +1.0 MB     disk16


/dev/disk17 (disk image):

   #:                       TYPE NAME                    SIZE       IDENTIFIER

   0:                            untitled               +6.3 MB     disk17


/dev/disk18 (disk image):

   #:                       TYPE NAME                    SIZE       IDENTIFIER

   0:                            untitled               +524.3 KB   disk18


/dev/disk19 (internal, physical):

   #:                       TYPE NAME                    SIZE       IDENTIFIER

   0:      GUID_partition_scheme                        *121.3 GB   disk19

   1:                        EFI EFI                     209.7 MB   disk19s1

   2:                  Apple_HFS Untitled                121.0 GB   disk19s2


-bash-3.2# diskutil cs list

No CoreStorage logical volume groups found

 

[Weaselboy]

@Weaselboy and others if possible to help?

This is a little worrisome because diskutil list is not showing the 1TB hard drive. When booted to Sierra, can you start Disk Utility and see the hard drive at all?

Was there something wrong that prompted you to do this? I'm thinking maybe the hard drive is bad.

 

[oliverd]

This is a little worrisome because diskutil list is not showing the 1TB hard drive. When booted to Sierra, can you start Disk Utility and see the hard drive at all?

Was there something wrong that prompted you to do this? I'm thinking maybe the hard drive is bad.

i can see HD 123GB as flash storage...and nothign else.

At some point iMac froze, force restarting using power ... loading was slow. Wanting to backup few GBs of things I didn;t already ended up impossible because most of the files were corrupted, or trasnfer was very slowand so ... trying to load to recovery boot wasn;t working only network recovery was showing so itried dozen of things, at some point i had Macintosh HD and SSD separate...at some point i deleted CS to be able to repair (red letter---apple suugestion..that was fine too..but installing was not possible --writing to disk wasno possible..so i again tried somehting else...and another things..and I have no idea any more..so i basically killed it. ?

-if HDD is bad/died, should I simply install Sierra again to 123GB SSD... and use it till i buy new machine in the future.?

Thanks for responding @Weaselboy

 

[Weaselboy]

-if HDD is bad/died, should I simply install Sierra again to 123GB SSD... and use it till i buy new machine in the future.?

Yeah... what you are describing there does sound like the hard drive died on you.

Sure, it will run just fine on the SSD until can fix or replace. Won't hurt a thing.

 

[oliverd]

OK, I'll run Sierra on SSD for some time than. thank you @Weaselboy

 

[oliverd]

Hi @Weaselboy me again, just wanted to ask if this means something promissing? (please see attached screenshot) .

At some point on Monday I actually sow in Disk Utility APPLE 1TB hdd , and APPLE SSD defused off-course, I went to terminal and "diskutil cs list" and received that huge list with all the info (I do not have it saved), than I went to Disk Utility to repair it, and I have received message to restart in Recovery mode to repair permissions, but restarting in Recovery mode I haven't seen the APPLE 1TB in sidebar anymore and "diskutil cs list" while in recovery was "no core storage etc.." only SSD 123GB was present... When I start Mac I go to Disk Utility to double check if it will appear again but it doesn't even after crt+alt+P+R etc..
--
Current situation as on the screenshot, In System report > SATA I can see that. Does it mean that it is still possible to revive it somehow with terminal (if yes is there any command I could try), or it is probably severely damaged and I should stop thinking about it
Thanks again Weaselboy.
Oliver

Yeah... what you are describing there does sound like the hard drive died on you.

Sure, it will run just fine on the SSD until can fix or replace. Won't hurt a thing.

 

[Weaselboy]

Does it mean that it is still possible to revive it somehow with terminal (if yes is there any command I could try), or it is probably severely damaged and I should stop thinking about it

Nah... with it just sporadically showing up like that, I still think it is a goner.

 

[oliverd]

oh well thanks Weaselboy