Create bootable ISO for High Sierra Installer

I needed to create a High Sierra ISO for use with VirtualBox – which worked successfully.

The following method worked successfully on both Sierra and High Sierra systems.

The High Sierra installation files can be downloaded from the App Store when using a Mac or Hackintosh. I usually download a fresh copy of High Sierra after each update release from Apple.

Open Terminal with Spotlight, or by navigating to the Utilities | Applications folder and click the Terminal.app

Enter the following lines into Terminal to create the ISO for High Sierra.

hdiutil create -o /tmp/HighSierra.cdr -size 5300m -layout SPUD -fs HFS+J

hdiutil attach /tmp/HighSierra.cdr.dmg -noverify -mountpoint /Volumes/install_build

sudo /Applications/Install\ macOS\ High\ Sierra.app/Contents/Resources/createinstallmedia --volume /Volumes/install_build

mv /tmp/HighSierra.cdr.dmg ~/Desktop/InstallSystem.dmg

hdiutil detach /Volumes/Install\ macOS\ High\ Sierra

hdiutil convert ~/Desktop/InstallSystem.dmg -format UDTO -o ~/Desktop/HighSierra.iso

mv ~/Desktop/HighSierra.iso.cdr ~/Desktop/HighSierra.iso

A usable ISO should be created if no errors are encountered.

To use these commands in a script file, I would suggest using the && operator to chain the commands together. When the && operator is used the next command is run if and only if the preceding command exited without errors.

hdiutil create -o /tmp/HighSierra.cdr -size 5300m -layout SPUD -fs HFS+J && hdiutil attach /tmp/HighSierra.cdr.dmg -noverify -mountpoint /Volumes/install_build && sudo /Applications/Install\ macOS\ High\ Sierra.app/Contents/Resources/createinstallmedia --volume /Volumes/install_build && mv /tmp/HighSierra.cdr.dmg ~/Desktop/InstallSystem.dmg && hdiutil detach /Volumes/Install\ macOS\ High\ Sierra && hdiutil convert ~/Desktop/InstallSystem.dmg -format UDTO -o ~/Desktop/HighSierra.iso && mv ~/Desktop/HighSierra.iso.cdr ~/Desktop/HighSierra.iso