Thanks for the link!
I'm all for APFS and it will definitely benefit SSDs, but am waiting for DiskWarrior to fully support it. My understanding is that Apple hasn't released full specs for APFS that Alsoft (DiskWarrior's developer) needs.
Another thing to consider is that older Macs that can't run High Sierra or above won't be able to read any APFS-formatted disks.
I felt the same way about the lack of an APFS capable version of Disk Warrior, and decided to install HS without converting to APFS. Using the info below (accumulated from various sources on this forum), everything went fine.
Install HighSierra without converting to APFS
Make sure the installer file is in the /Applications folder, run one of the commands below from the terminal.
/Applications/Install\ macOS\ High\ Sierra.app/Contents/Resources/startosinstall --converttoapfs NO
/Applications/Install\ macOS\ High\ Sierra.app/Contents/Resources/startosinstall --applicationpath /Applications/Install\ macOS\ High\ Sierra.app --agreetolicense --converttoapfs NO --nointeraction
Note: When you enter your password in Terminal, no text will be displayed, giving the impression that Terminal isn’t accepting your input. This is a security feature to ensure prying eyes can’t see your password as it is typed.
You’ll be presented with the license for using macOS High Sierra. You can agree to the license terms by entering a capital A at the prompt.
The startosinstall script will start copying needed files to the target disk (in this example, the current startup disk). You’ll see Terminal counting up to one hundred. When it reaches 100, all the needed files will have been copied, and your Mac will reboot and start the actual installation of the new operating system without converting the startup disk to APFS.
To specify what drive to install macOS High Sierra on, other than the startup drive, you need to add the following to either of the Terminal command lines listed above:
— volume /path to the volume you wish to use
An example for installing macOS High Sierra on a drive named HighSierra without converting the target volume to APFS would be:
sudo /Applications/Install\ macOS\ High\ Sierra.app/Contents/Resources/startosinstall –applicationpath /Applications/Install\ macOS\ High\ Sierra.app –converttoapfs NO –volume /Volumes/HighSierra
This would force the installation to occur on a volume named HighSierra. An easy way to enter the actual pathname to the drive you wish to use is to enter the command in Terminal without the actual pathname, so the command would end after — volume (make sure there’s a space after the word volume). Now drag the drive from the Finder and drop it on the Terminal window. Terminal will add the actual pathname to the drive for you. All that’s left to do is press enter or return.
By using the startosinstall command from within Terminal, the choice to convert to APFS or leave the target drive’s format unchanged is entirely up to you.
