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User profile for user: DmitryV
DmitryV Author
User level: Level 1
8 points

Need help with fixing Fusion Drive of iMac

Hello!

i have iMac 27 2019

After reinstall OSX Catalina my Fusion drive been divided into SSD and HDD.

I tried fixing Fusion Drive - reboot iMac in Recovery mode and use the Terminal.


I try command


diskutil resetFusion


It not work for me and give error


Error: -69877: Couldn't open device


I think it is problem with SDD disk (for my Disk0). I try unmount it by command


diskutil unmoutDisk disk0


and give error:


Unmount of disk0 failed: at least one volume could not be unmounted

Unmount was dissented by PID 0 (kernel_task)


What can i do now and how i can to fix my Fusion Drive?

I will be glad of any help.


iMac Line (2012 and Later)

Posted on May 5, 2020 4:27 PM

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User profile for user: DmitryV
DmitryV Author
User level: Level 1
8 points

Posted on May 6, 2020 3:07 AM

Before tried to fix Fusion Drive i already wrote this article.

Information was helpful, but not full.

For complete unmount disk0, it is not enough to boot in the recovery mode.

You need to boot from bootable USB drive, and only after this you can try to fix FusionDrive.

It works for me.


Нowever, thank you for fast answer.

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User profile for user: DmitryV
DmitryV Author
User level: Level 1
8 points

May 6, 2020 3:07 AM in response to leroydouglas

Before tried to fix Fusion Drive i already wrote this article.

Information was helpful, but not full.

For complete unmount disk0, it is not enough to boot in the recovery mode.

You need to boot from bootable USB drive, and only after this you can try to fix FusionDrive.

It works for me.


Нowever, thank you for fast answer.

Reply
User profile for user: leroydouglas
leroydouglas
Community+ 2024
User level: Level 10
189,090 points

May 5, 2020 4:57 PM in response to DmitryV

DmitryV wrote:

Hello!
i have iMac 27 2019
After reinstall OSX Catalina my Fusion drive been divided into SSD and HDD.
I tried fixing Fusion Drive - reboot iMac in Recovery mode and use the Terminal.

I try command

diskutil resetFusion

It not work for me and give error

Error: -69877: Couldn't open device

I think it is problem with SDD disk (for my Disk0). I try unmount it by command

diskutil unmoutDisk disk0

and give error:

Unmount of disk0 failed: at least one volume could not be unmounted
Unmount was dissented by PID 0 (kernel_task)

What can i do now and how i can to fix my Fusion Drive?
I will be glad of any help.



How to fix a split Fusion Drive - Apple Support


Reply

Need help with fixing Fusion Drive of iMac

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