Mac – How to exclude a hard drive from Time Machine backup history

If your drive is corrupted in any way you probably don't want to use it for backup purposes any more, unless the data is not of great value to you.

Apple does not allow an easy transfer from drive to drive regarding backups. I think this is due to the way TimeMachine works (As stated in this apple discussion thread)

Now how to do it anyways ? I would simply use command line power. If you're the admin of the computer, you can simply open Terminal and do something along this:

• sudo -s
• rsync -avhW --progress < Drag and drop external Hard Drive here >< Drag and Drop DropBox folder here >

or

• mv < Drag and Drop backup folder here >< Drag and Drop DropBox folder here, ending with a "/">

sudo -s puts you in the super-admin position, so you have full access to the system

rsync will sync the content and you can stop and continue at any time. mv will move the whole thing at once.

You should be able to drag and drop any folder within the backup to any folder on you internal/other external drive. Only the "Machine.backup" folder is protected.

Turn off Time Machine with the switch in System Preferences, then remove the Backups.backupdb from drive A.

Time Machine should recognise that the disk is no longer a Time Machine backup destination, but if it doesn't, delete .com.apple.timemachine.donotpresent from the root of the disk.