macOS 11 Big Sur or Later Headless Virtual Machine Setup


From macOS 11 Apple introduces greater virtualisation capabilities including accelerated graphics support for macOS 11 and newer guests through Metal. When Parallels Tools is installed the macOS virtual machine will gain the new graphical features, however this may introduce problems for some virtual machines:

If your macOS 11 or newer virtual machine is intended for headless, or autostart use the new graphics capabilities will prevent the virtual machine from starting; it will fail on virtual hardware initialisation. This is a problem in scenarios such as:

  • Running macOS Server in the background via auto start
  • Starting the virtual machine via an ssh session
  • Using a headless virtual machine to provide services to remote clients for example UNIX server software installed through Mac Ports or Homebrew.

Solutions

  1. Setup the macOS 11 or newer virtual machine but do not install Parallels Tools: if you do install these uninstalling them alone will not fix issues with headless starts so use the next option.
  2. Install Parallels Tools in the virtual machine, shutdown rather than rebooting if working remotely via ssh, then issue the following command to disable Apple’s Metal Paravirtualized Graphics device and use the non accelerated Parallels device instead:
    • prlctl set "Your macOS VM Name" --video-adapter-type parallels

You can now start your macOS 11 or newer virtual machine via ssh and prlctl, or autostart on macOS host startup as usual without the enhanced graphics capabilities.