Just format to APFS encrypted? Instead of enabling FV later on?

[quaresma]

Hi,

I want to clean install High Sierra. The last time I did it, i formatted to APFS and enabled FV after OS installation. Remaning time for encryption was 14 hours vs 20 minutes on Sierra!

This time, if I just format to APFS encrypted during clean install, FV will be enabled from the start, and I won't have to wait 14 hours for it to complete?

This is something I read on apple forums.

What's the difference between enabling FV after OS installation has completed vs. formatting directly to APFS encrypted? Which option is the most secure?

Thanks

 

[Weaselboy]

This time, if I just format to APFS encrypted during clean install, FV will be enabled from the start, and I won't have to wait 14 hours for it to complete?

It will be enabled, but it won't work properly. What you want to do is format APFS UNencrypted then enable FV after the install.

When FV is enabled it changes the boot process so your Mac boots from the recovery drive and presents a login screen. Once you login, the drive is unlocked and the boot process is handed off the main drive.

If you format with encrypted first, the FV setup steps will not occur and the login process will not work properly.