If you want to switch to a different Time Machine backup drive, use these steps to move your existing backups.
Check the format of your new backup drive
- Connect the new backup drive to your Mac.
- Open Disk Utility (located in the Utilities folder).
- In Disk Utility, select the new drive's icon to make sure it has a GUID partition and is formatted as Mac OS Extended (Journaled). You can check this from the "Format:" line at the bottom of the Disk Utility window. If your new backup drive is not formatted this way, reformat it, selecting the option for Mac OS Extended (Journaled) with a GUID partition. Back up any important data from your new drive before you format it.
Set permissions on your new backup drive
- Open a new Finder window.
- In the sidebar of the Finder window, click the icon of the new backup drive.
- Choose Get Info from the File menu.
- Make sure "Ignore ownership on this volume" at the bottom of the "Sharing & Permissions" section of the Get Info window is deselected (unchecked).
Temporarily turn Time Machine off
- Choose System Preferences from the Apple menu.
- Click the Time Machine icon in the System Preferences window.
- Slide the Time Machine switch to Off.
Copy your backup data from your original drive to your new drive
- Open a new Finder window. In the Finder sidebar, click the icon of the original backup drive.
- Open a new Finder window. In the Finder sidebar, click the icon of the new backup drive.
- Drag the folder "Backups.backupdb" from the original backup drive to the top level of the new backup drive.
- Enter an administrator name and password, then click OK to start the copying process.
Copying your backup data might take some time to complete, depending on the size of your backup.
Set Time Machine to use your new drive
- After the copy has finished, open Time Machine preferences from System Preferences.
- Click Select Disk in the Time Machine preferences window.
- Select the new backup drive, then click Use Backup Disk.
Your Time Machine backups are now be saved on your new backup drive.