Can't Delete Raid Set, As 1st Step In Restructuring, Reformatting. Tried Everything, I'm Stumped.

Question

Hi Folks,

Problem:

I can't delete, reformat, or restructure my raid set. See my screen grabs for error messages.

Details:

I have two external firewire drives that I use for back up.

Both externals are 1,500 GB

I have them joined together ( jbod / connaconnected ) because just one drive isn't big enough for Time Machine.

There is one small partion carved out of the 3000 Gb raid set, that I use as an emegency boot drive.

What I have tried so far:

• Deleting the contents of all the drives, so that there is nothing that the system uses on there.

• Booting from the install disk, and launching Disc utils from there.

• Unmounting the drives

• Using the Raid Utility app. Thats only usefull with a Raid card which I don't have.

• Deleting the Individual drives first, then the raid stsructure in disc utils.

• Deleting the raid set first.

• Reformatting the drives.

Here are my screen grabs, in case the max forum size is not readable

Here are my screen grabs, posted at the max forum size

Thanks!

Mac Pro, Mac OS X (10.6.8), 6 Core

Posted on Jul 14, 2012 9:23 AM

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Answer 1

Level 1

9 points

I had this problem with OS X Sierra. The solution for me, was to erase the disk using command line (terminal) diskutil.

Like this:

diskutil eraseDisk JHFS+ Untitled /dev/disk#

Where # is your disk number, to find out which one is it, use the command "diskutil list". It will show as the one that says RAID-something.

Now, first time you run it, it will fail, but it will destroy the raid set. So, run it again, and it will erase the disk.

Hope it works for anyone having the problem!

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