I want to use "startosinstall" so that I can install macOS Catalina onto an external hard drive in order to preload MacOS onto multiple SSD's quickly.
I've researched into this and have found websites such as Erase All Contents And Settings - erase and reinstall macOS in situ which suggest using:
/Applications/Install\ macOS\ Catalina.app/Contents/Resources/startosinstall \
--applicationpath /Applications/Install\ macOS\ Catalina.app \
--agreetolicense --nointeraction --volume /Volumes/External\ Macintosh\ HD
I've tried running the above but have had no success and always find that I get this returned:
--applicationpath, a path to copy of the OS installer application to start the install with.
--license, prints the user license agreement only.
--agreetolicense, agree to license the license you printed with --license.
--rebootdelay, how long to delay the reboot at the end of preparing. This delay is in seconds and has a maximum of 300 (5 minutes).
--pidtosignal, Specify a PID to which to send SIGUSR1 upon completion of the prepare phase. To bypass "rebootdelay" send SIGUSR1 back to startosinstall.
--converttoapfs, specify either YES or NO on if you wish to convert to APFS.
--installpackage, the path of a package (built with productbuild(1)) to install after the OS installation is complete; this option can be specified multiple times.
--eraseinstall, Erase all volumes and install to a new one. Optionally specify the name of the new volume with --newvolumename.
--newvolumename, the name of the volume to be created with --eraseinstall.
--usage, prints this message.
Example: startosinstall --converttoapfs YES
but can't seem to actually get anything to run.
If anyone could provide me with some working code or show me how to solve this problem, I would be eternally grateful.
Thanks for your help