I recently converted one of my Apple RAID drives into an encrypted CoreStorage logical disk on 10.8. This is a great way to leverage Time Machine with encrypted backups. Here are the steps I used. Note, this process will destroy data on the disk, so please backup your files first.
First, I used the command
diskutil cs list to get a listing of my current CoreStorage logical groups. From the screenshot below you can see that I’ve got one physical disk and one logical disk group.
If I do a
diskutil list you can see that I’ve got two physical disks and a single RAID logical volume made up of those two disks.
So the first thing I want to do is create a new CoreStorage Logical Disk using the RAID Logical Volume. In my case, Disk5 is the logical volume. In my case I’m creating a logical group called myNewLvg.
diskutil cs create myNewLvg disk5
Warning, this is a destructive operation, it will completely destroy any data on your RAID partition.
Next I want to create a new file system on the logical volume but I’ll first need to grab its GUID or UUID, so I need to do another
diskutil cs list
Lastly, we’ll need to create a new file system on the new logical volume. So in my case using the GUID from the previous step, I’d enter:
diskutil cs createVolume E7E24D74-1F0F-44D7-BFC6-7A818CCDCCD5 jhfs+ LacieRAID 100% -stdinpassphrase
Not only will this format the disk for HFS+ journaled, but it will prompt for a password to encrypt the disk. Make sure you put the password in a safe place because if you loose it, you’ll never see your data again.
And that should be all, the disk should be encrypted and ready to go. In my case, the whole operation took only a minute from start to finish. Now I’ve got Apple SoftRAID with a CoreStorage encrypted volume.