List Listening Ports lsof -P -n | grep -i listen -P "inhibits the conversion of port numbers to port names for network files" -n "inhibits the conversion of network numbers to host names for network files" grep-ing by listen lists only those ports that we're serving Install macOS Catalina from Scratch https://appleinsider.com/articles/19/10/09/how-to-create-a-bootable-macos-catalina-installer-on-a-usb-drive