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Help split fusion, only sees the HDD

After I did the: diskutil coreStorage delete

Even after reinstalling macos, it now says "No CoreStorage logical volume groups found"

Hope someone can help, to make it worse my time machine just crashed, so I have no backup of the machine.
(what a day).
 
Get back into Terminal and run each of these two commands then tell me the output of both.

Code: 
diskutil list

diskutil cs list

Do you want to rebuild the Fusion drive?
 
Weaselboy, thank you!

diskutil list:

o: GUID_partition_sceme *1.0tb Disk 0
1: EFI EFI 209,7mb disk0s1 209,7 mb disk0s1
2: Apple_HFS without name 999.3 gb disk 0s2
3: Apple_Boot Revovery HD 650.0 mb disk0s3

And allot of disk images (biggest one listed is 2.1 gb, rest is kb or mbs)

diskutil cs list

No CoreStorage logical volume groups found"

DryMfnP.jpg



Before I did the diskutil coreStorage delete there was a logical volume group.


And no, I would love to have them seperate, but right now there is no SSD component showing at all - so just getting the SSD part back where I can see it would make my day :)

It litterally seamed like the ssd just disapeared after the "diskutil coreStorage delete" :(
 
Last edited:
psymac said:
Have you tried this?

https://support.apple.com/en-us/HT207584
Click to expand...

Thank you for writing, but I don't think you spotted the exact problem mate :)

Or am I totally overlooking something?

It seams to me like there is no longer any identifier for the ssd? it's like it totally disappeared?

Thanks :)
[doublepost=1511823786][/doublepost]Your second guide is exactly what I did, and was what made the ssd disapear. ;)
 
Ok, tried this?
“Boot into Recovery HD by restarting and then holding down Command-R until you see the system start to load. You can then run Disk Utility from the menu that appears and try to fix the Fusion drive.

If Disk Utility displays an error, restart, hold down Command-Option-R, and follow Apple’s instructions on its support page to use Internet Recovery.”
 
I have tried it from both recovery, usb and everything.

1) The Disk Utility does not see the SSD at all any longer (at all).
- So it can't fix anything. (I have tried everything, delete, repair - everything).
- It does not display the red error or anything, it just sees it as a 1 tb normal hdd.

2) The last reply to Weaselboy was done from booting into recovery and then running the terminal from there.
So that does not see it either.

Is there anyway to do a firmware reeset or something?
 
We don't have those in denmark - but I might have to buy a cheap external ssd for it - and run it from there - I guess :(
 
Heliotropen said:
It litterally seamed like the ssd just disapeared after the "diskutil coreStorage delete"
Click to expand...
Hmmm... not good. Running that cs delete command would in no way harm the SSD, so you have something else going on. The diskutil list command it not even showing the SSD physical drive, and no matter how you mucked this up, you should be able to see it.

Don't be concerned about all those other small volumes, that is normal and just little virtual drives created by the recovery process.

Can you try a command-option-r boot to Internet recovery and see if the SSD shows up there?
 
I have tried the internet recovery and it does not show up there.

Something I noticed if I run first on it, is that first aid writes:
fschk_hfs -fy -x /dev/rdisk0s2

Clearly it's /dev/rdisk0s1 that is missing.

It seams really weird.

Im sure it was fusion before and that it contained an SSD (I saw it just before I did the coreStorage delete).
 
Your trouble concerns me because I’m planning to split the fusion drive on my new iMac when it comes next week.

More Googling this problem may be needed, otherwise pay for telephone technical support from Apple?

Another option is to go ahead and rebuild the hard drive with internet recovery and see if you can see the SSD after that.
 
"rebuild the hard drive with internet recovery" ? I reinstalled macos from internet recovery.
And I ran all the disk utility options from there also ...

So how do you suggest I try that ?
 
Heliotropen said:
Clearly it's /dev/rdisk0s1 that is missing.
Click to expand...
No... disk0 is the hard drive and disk0s2 is the main Uden navn partition on the hard drive. Normally the SSD would show up as disk1. I think you have some hardware issue here causing the SSD not to show up.

If you want to get up and running just for now, you can format the hard drive from Internet recovery and install the OS there. At least that would get you running until you can take it in somewhere to get the hardware issue with the SSD diagnosed.
 
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Hmm it’s possible, the machine has been really slow.

But it’s suspectable that it disapears just after the delete.

I’m running macos from the hd now, but the disk without the ssd is a drag.

Dont think getting it diagnosed is an option. It’s expensive here in denmark. And it’s bought second hand.

If I can’t diagnose ot myself, I will probably have to look for a cheap extetnal ssd and boot from that.

This entire thing really sucks :(
 
You haven’t said what model iMac you have, and if you have Thunderbolt 2 or 3. More external closures are coming online and prices coming down for Thunderbolt 3, which is going to be faster than your fusion drive.

http://barefeats.com/hard226.html


Also, if you’re handy and brave, the other option is to open the iMac and replace the ‘dead’ SSD blade drive. Also replace the internal SATA HD while you’re at it with a relatively large SATA SSD.
[doublepost=1511833989][/doublepost]I just thought you might want to call the memory experts at OWC and see if they may be able to help you.

https://www.macsales.com/
 
It’s a late 2013 27”.
[doublepost=1511834686][/doublepost]I dont want to use to much energy or money on it.

I could but a blade on eBay or something but 1) I’m scared of opening it up 2) if it’s the controller not the disk that is broken, I would have to kill myself.

I’m in denmark, so not fond on calling US Experts.
 
UPDATE: So I talked to apple care, they ran all kind of diagnotics and commands on it.

They seam to think that the ssd is either dead (or need to get replugged) - and that the defusion was just the last step for it.

To be fair it runs faster now (200 / 200) than before - so the ssd was probably already dead.

I'm not going to use the money to get it diagnosticd and repaired - beyond that it is a late 2013 afterall - and money is tight at the moment.

Either I'm going to run it from the slow HDD (that seams to work OKAY).
Or plugin in an external SSD - not sure if I can find a thunderbolt I can afford, or if it will be USB3 (with no trim probably).
 
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OP:
Don't bother with Thunderbolt. No speed increase at all. Too much money.
Get a USB3 SSD, plug it in, and set it up to become "your external boot drive".
Easy enough to do.

I'd suggest a Samsung t5.
Even 256gb will do fine.
 
Its indeed allot of money for that old ****, but the USB 3 does not TRIM ... :)

Right now I'm getting read / write about 200 / 200 in black magic:

How slow is that to be thought of? how much faster will an extern solution be?

(Most of my living is made from webdevelopment / webdesign - on this old thing).

I can get a samsung t5 usb 3 for about half the price of an Transcend StoreJet 500 256 GB (thunderbolt).

And extern disclosure with an ssd will cost 3-4 times of the t5.
 
Last edited:
Today I can actually get a Transcend StoreJet 500 256 GB... for the same price almost as the t5 usb 3.
So I'm going for that ... unless someone wants to advice me against that exact drive? ... (will give it an hour).
 
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Heliotropen said:
Today I can actually get a Transcend StoreJet 500 256 GB... for the same price almost as the t5 usb 3.
So I'm going for that ... unless someone wants to advice me against that exact drive? ... (will give it an hour).
Click to expand...
That drive will work just fine.
 
Great thank you allot.

They have an offer on ram also ... right now I have 8gb in it.

Will it help to add 2x4 gb more now I'm at it?

The ram was was thinking about was these - since they are very cheap:

"V7 DDR3 8 GB: 2 x 4 GB SO DIMM 204-PIN 1600 MHz / PC3-12800 CL11"

They hold these specs:

Product Description V7 - DDR3 - 8GB: 2 x 4GB - SO DIMM 204 PIN
Product-RAM memory
Capacity 8 GB: 2 x 4 GB
Memory Type DDR3 SDRAM - SO DIMM 204 PIN
Upgrade Type Generic
Data Integrity Check Non-ECC
Speed 1600 MHz (PC3-12800)
Search Time Timings CL11
Features Low Voltage, not buffered
Voltage 1.35 V
Manufacturer Warranty 10-Year Warranty

But I'm not sure they are high enough quality ?
 
Heliotropen said:
Will it help to add 2x4 gb more now I'm at it?
Click to expand...

Here is how to tell... reboot then use it as you would normally most of the day. Then open Activity Monitor and click on the memory tab and look at memory pressure at the bottom. If that is in the green, you will likely not see much if any benefit from more RAM.

Screen Shot 2017-11-30 at 1.00.46 PM.png
 
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