How to create a bootable macOS Catalina Installer from MacOS. See https://bootableinstaller.com

create-bootable-installer-for-macos-catalina.sh

#########################
# bootableinstaller.com #
#########################

set -e
set -u

# Create an empty
hdiutil create -o /tmp/empty -size 8400m -volname "Catalina" -layout SPUD -fs HFS+J

# Rename to .img since this isn't a compressed disk image
mv /tmp/empty.dmg /tmp/catalina.img

# Mount the empty disk image
hdiutil attach /tmp/catalina.img -noverify -nobrowse -mountpoint '/Volumes/Install macOS Catalina/'

# Create the installer image
sudo /Applications/Install\ macOS\ Catalina.app/Contents/Resources/createinstallmedia --nointeraction --volume '/Volumes/Install macOS Catalina/'

# Detach the installer
hdiutil detach '/Volumes/Install macOS Catalina/'

# This is actually already in the correct format
mv /tmp/catalina.img catalina.iso

# Many thanks to https://support.apple.com/en-us/HT201372

I'm not sure if You are author of website: https://bootableinstaller.com/macos/#macos but link there is broken for this file

Thanks. It's fixed now.

…

On Thu, Oct 8, 2020 at 11:42 AM Patryk Ptasiński ***@***.***> wrote: ***@***.**** commented on this gist. ------------------------------ I'm not sure if You are author of website: https://bootableinstaller.com/macos/#macos but link there is broken for this file — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <https://gist.github.com/fec04e2dc405862a0d9542c95df80cef#gistcomment-3482413>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAA57T5Y3W6Y6SNLZFN7AGDSJX2XLANCNFSM4SJBYLRQ> .