How to move home folder to external SSD on SONOMA 14.7.2

You can move it, but your experience may be less than stellar. While it worked ok in the past, since Sonoma, people have experienced many problems.

You also must keep an admin-capable user on the internal SSD because the attachment to your external drive will break when it is not available at login.

There are better ways to accomplish what you want. All of the large storage Libraries can be set to exist on the external drive, Photos, Movies, TV, Music, etc. Mail cannot be set to exist on another drive.

If you wish to move your home folder,

Erase and format the drive APFS. You must enable permissions on the external drive by turning off "Ignore Ownership…" checkbox in Get Info. Create a folder on the drive to hold the new home folder. Maybe even Add another APFS volume to the drive in Disk Utility to use as the Home folder storage area. You could then just Ignore Ownership on that Volume.

Copy your current home folder to the external drive.

See this article on changing user name. Follow all the instructions precisely. If you fail to create a new admin user and log out of the user you are changing, you will lock yourself out of your Mac. When you get to the part about renaming the home folder, set its full path, e.g., /Volumes/MyNewHomeDriveFolder/shortusername. You don't need to change the short user name, just the path to the new home folder.

I highly recommend not deleting the home user folder from the internal boot drive so if something goes wrong, then you may still be able to log into your user account although none of your recent data will be there. In the past when a minor macOS Monterey update patch broke external home folders, the system recreated a new home user folder on the internal boot drive...which caused problems for people to redirect the system to use the external home user folder. The fix was not easy to perform & was not intuitive...it was weeks before someone posted exact instructions for fixing the broken system so others with less experience could try fixing their system without reinstalling. Some people were left with a broken system for a long time because they couldn't fix it. Then another couple of minor OS update patches broke things a few more times before Apple addressed the issue many months later. You are literally on your own with such a custom setup.

Plus I have seen some posts on this forum where Time Machine will refuse to restore to a home user folder located anywhere but the default location on the internal boot drive.

You would do much better by moving the items with large amounts of data to the external data drive instead of moving the whole home user folder. Apple has articles for relocating many libraries which usually are where most large amounts of data are stored, such as Photos, Music, Videos, etc. Since Apple has actually published support articles describing the procedure, it means that Apple should be actively supporting that configuration unlike the custom configuration of relocating the home user folder.

In my own personal experience, macOS these days does not like to encounter custom configurations. It is best to stay as close to the default configuration as possible unless Apple actually provides official instructions for a custom configuration. YMMV

HWTech wrote:

I highly recommend not deleting the home user folder from the internal boot drive

+1 👍 Totally agree. One can get into an awful lot of trouble moving a home folder, some of which may be apparent immediately, other problems showing up later. Easily a setup for disaster.

It is much better practice to store data on the external drives. And it's easy enough to relocate things that typically take up a lot of space, like iTunes/Music library, Photos library, Final Cut libraries, etc.