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I would like to create a logical volume group (LVG) with two physical disks.


The command:

diskutil coreStorage create LVGNAME /dev/disk1 /dev/disk2


Started CoreStorage operation  
Error: -69886: Invalid request

More info

Tested with two USB drives, two SATA disks (one internal, one external FireWire 800).

I can format them with Disk Utility.

I can unmount without a problem.

MacBookPro8,2 with Mac OS X 10.7.4 (same with 10.7.5)

diskutil cs list
No CoreStorage logical volume groups found

With one disk alone I can create a non-composite LVG:

diskutil coreStorage create LVGNAME /dev/disk1  
Started CoreStorage operation  
Unmounting disk1  
Repartitioning disk1  
Unmounting disk  
Creating the partition map  
Rediscovering disk1  
Adding disk1s2 to Logical Volume Group  
Creating Core Storage Logical Volume Group  
Switching disk1s2 to Core Storage  
Waiting for Logical Volume Group to appear  
Discovered new Logical Volume Group "05F84BFF-DC4D-4DD2-94DB-116FC7F8C804"  
Core Storage LVG UUID: 05F84BFF-DC4D-4DD2-94DB-116FC7F8C804  
Finished CoreStorage operation
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Error -69886 also features in a question that's currently in Super User: Removing encrypted partition on Mac os X does not work. – Graham Perrin Mar 30 '13 at 15:00
Replicated the problem on 10.7.5 with DMG files. Worked in 10.8.x – Wing Tang Wong Apr 10 '13 at 19:33

Operating system

Can you reproduce the problem with Mac OS X 10.7.5?

If -69886 arises from a failure to unmount

Expanding upon a hint in an answer to a linked question, try this before the Core Storage operation … for the device that apparently can't be added:

diskutil unmount /dev/disk2s2

– then if the unmount fails, to discover what's open:

sudo lsof /dev/disk2s2


Currently limited by Apple to Mac OS X 10.7.4: diskutil(8) OS X Manual Page

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I've correctly unmounted disk without problems. lsof return nothing. The linked answer does not help me in this situation because I don't have LVG listed. – MnO Mar 30 '13 at 15:34
I've tested this on 10.7.5 and the error is there as well. – Wing Tang Wong Apr 10 '13 at 19:43

Try booting from a USB drive.

Internet Recovery uses the local disk to temporarily store the image, which it won't let you delete. via

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