To prevent problems with your virtual machines and to save space on your backup media, you should not back up virtual machines with Time Machine.
If you do not exclude virtual machines from Time Machine backups, Time Machine can back up a virtual machine while it is running. Restoring from this kind of backup would overwrite your current virtual machines with versions that are incomplete and potentially damaged. For the recommended method of backing up virtual machines, see Copy a Virtual Machine to External Media.
- Open the Mac's System Preferences and click Time Machine.
- Click Options.
- Click the add (+) button at the bottom of the Do not back up list.
- Browse to your Documents folder on the Mac, select the Virtual Machines folder, and click Exclude.
The Virtual Machine folder appears in the Do not back up list, and displays the total memory used by all your virtual machines.
- Click Done, and close the Time Machine window.