Sitting it aside is especially important as that ensures you don’t accidentally damage the the backup while installing Linux. Once the system comes back up eject the backup disk and sit it aside. Once you have verified everything looks good go into System Preference again, set the startup disk back to the internal drive, and reboot. By not entering your password you can ensure that everything you see is from the backup and not the internal one. If your internal drive is encrypted you’ll be prompted for its password when you login… don’t enter it. Once your backup completes go into System Preferences and change the startup disk to the external drive and reboot. When you “Erase” the disk be sure to pick “Mac OS Extended (Journaled)” regardless of how your internal drive is formatted.

Select the drive, not one of the partitions on it.In the top left of Disk Utility click the button above “View” and tell it to show all devices.When you go to format your external hard drive there are two things you need to be sure and do to have the best chance at success: Be sure to put the backup on an external hard drive. It’ll take care of backing up all your files along with the special partitions needed to make things work including the recovery partition. One way to do this is to use Carbon Copy Cloner. Full BackupĪny time you start messing with the partitions of existing drives its a good idea to have a full backup you can fall back on as its really easy to have your drive become unbootable. The hard drive is formatted APFS and has File Vault turned on.īefore beginning I suggest reading this entire post to see how involved it is or, at a minimum, read the known issues at the bottom. This is a step-by-step walkthrough for dual booting a MacBook Pro (Mid-2015 aka MacBookPro11,5) that already has macOS High Sierra on it with Linux Mint. Dual Booting macOS High Sierra and Linux Mint

Dualboot macbook