Backup Your iPhone to an External Drive

How to Link Your iPhone Backup to an External Drive
==================================================================
First! (if not already) create a backup of your iPhone to your internal hard-drive AND

Grant Terminal full disk access. How?

    System Preferences > Security & Privacy > Privacy Tab

    Select Full Disk Access (folder icon) from the left sidebar

    If you can’t make any changes, then click/toggle the lock (icon) and enter user password.

    If Terminal is not listed in the window, then click the ‘+’ icon and find and select Terminal within Applications folder.

    Then check the checkbox for Terminal. Toggle the lock and restart Terminal if it’s already open.

NOW, HOW TO INDEFINITELY BACKUP YOUR IPHONE TO AN EXTERNAL DRIVE
==================================================================
a. Open Spotlight (⌘ + SPACE) and search for Terminal

    Execute the following command in Terminal to create your Backup folder on your external drive:

        $ mkdir /Volumes/NAME_OF_YOUR_VOLUME/iPhone_backups

b. Using Terminal, copy your iPhone backups Backup folder to your external:

        $ mv ~/Library/Application\ Support/MobileSync/Backup /Volumes/NAME_OF_YOUR_VOLUME/iPhone_backups

c. Rename the original Backup folder (on your internal drive) by using Terminal to something like Backup-OLD

        $ mv ~/Library/Application\ Support/MobileSync/Backup ~/Library/Application\ Support/MobileSync/Backup-OLD

d. Here we execute the command to create a symbolic link (symlink) to your Backup folder on your external

        $ ln -s /Volumes/NAME_OF_YOUR_VOLUME/iPhone_backups ~/Library/Application\ Support/MobileSync

VERIFY AND TEST THAT THE SYMLINK EXISTS AND FUNCTIONS
==================================================================

a. In Finder, press command + shift + G (⌘ + ⇧ + G) then type or paste in the following location:

        ~/Library/Application\ Support/MobileSync

b. If the Backup folder within the MobileSync folder has a small arrow pointing inwards, then the symlink has been established.

c. Verify it now functions by performing another iPhone backup. After the backup, confirm that that backup is stored on your external.


====================================================================================================================================
If you’re unsure about something then please contact me and I’ll reply soon when convenient. Else, try googling.