delete CoreStorage Volume completely

[MikB]

I installed Yosemite on an external 3TB drive. I made a specific 300GB partition on it to hold the system and a second for data. Installation worked fine. However, according to Disk Utility in both Mavericks and Yosemite there is only a little more than 800GB available on the whole disk.

When I run

diskutil list; echo; diskutil cs list

it says there are no CoreStorage Volumes, but I knew from the Yosemite installation that there is one.

How can I get rid of the CoreStorage Volume even as OS X won't acknowledge there is one? Do I dare to delete and erase the complete drive from Disk Utility in Mavericks? It seems risky as it can't even show me the lost partition space.

Here's the output from the command above:

/dev/disk2
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *801.6 GB   disk2
   1:                        EFI EFI                     209.7 MB   disk2s1
   2:                  Apple_HFS X Drive                 320.1 GB   disk2s2
   3:                 Apple_Boot Recovery HD             650.0 MB   disk2s3

No CoreStorage logical volume groups found

 

[MikB]

I don't know how to solve your problem. Maybe you can read this article"Tips for Recover Lost Files on Mac (OS X Yosemite Included)". Hope this article will help you a little. Good Luck!
http://www.cisdem.com/resource/recover-lost-files-mac.html

Thanks, but I don't need to recover any files. I want to recover about 2.2 TB of drive space that OS X ignores.

 

[MikB]

Update

I ran

cat /dev/random > /dev/disk2

as su and all partitions are gone now.

At first, the available disk space was still only 801GB. After a while it showed up properly in Disk Utility as 3.0TB though. Excellent!

Thanks to Topher Kessler for posting the proper commands in How to fix deep formatting problems with OS X drives!

CoreStorage is great technology. Apple info still leaves a lot to be desired.