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Delete a disk set
When you no longer need a disk set, or want to remove individual disk members permanently from the set, you can delete the set.
Important: You can remove disks from a mirrored RAID set or concatenated disk set without deleting the set. To remove a disk from a striped RAID set, you must first delete the set which deletes all your data. Always back up before you delete the set.
Delete a disk set
When you delete a set, the data recorded on the disks is not deleted. For example, deleting a mirrored RAID set leaves each disk in the set with a copy of all the RAID data. When you delete a concatenated set, all the data is copied to the first disk of the set (as long as the first disk has enough disk space to store the data), providing a single volume with all the data.
Back up any important files.
In Disk Utility, select a disk set that you want to delete in the sidebar.
Click the Delete RAID button.
Click Delete.
Erase all the disks in a disk set
Back up any important files.
In Disk Utility, select a disk set that you want to erase in the sidebar.
Click the Erase button
in the toolbar.
Remove a disk from a disk set permanently
You can remove individual members of a mirrored RAID set or concatenated disk set. You can’t remove individual members of a striped disk set without first erasing the entire set. You can only remove the last member of a concatenated disk set.
Back up any important files.
In Disk Utility, select a disk set in the sidebar.
Select the member disk that you want to delete from the set.
Click the Remove button
.
Click Remove.