How to invoke a UEFI Shell (v2.2) on a Fusion Player virtual machine with Big Sur installed?

I tested the following UEFI Shell v2.2 binaries. Many of these were suggested on Arch Linux wiki website "Unified Extensible Firmware Interface" under the section "Obtaining UEFI Shell". Some binaries required extra effort to extract from the downloaded file.

• Arch Linux: The shellx64.efi file in the root directory of the mounted archlinux-2021.03.01-x86_64.iso file. See here for a list of websites where the ISO file can be downloaded.

• TianoCore EDK2 package: The Shell.efi file.

• EDK2 package from Arch Linux: The Shell_Full.efi and Shell.efi files in the usr/share/edk2-shell folder of the expanded edk2-shell-202011-1-any.pkg.tar.zst file, which can be downloaded from this website.

• rEFInd CD-R image: The shellx64.efi file in the EFI/tools folder of the mounted refind-cd-0.12.0.iso file. This ISO can be created by expanding the refind-cd-0.12.0.zip file, which can be downloaded from this website.

• OpenCore package: The OpenShell.efi file in the X64/EFI/OC/Tools folder of the expanded OpenCore-0.6.7-RELEASE.zip file, which can be downloaded from this website.

All of the above shell binaries, except for OpenCore, either had an faulty edit command or failed to display output when boot directly from the client firmware Boot Manager.

The shell binary from the OpenCore 0.6.7 release was chosen for use in this answer.

The steps to install the new UEFI shell are given below.

1. Download an OpenCore package: Open the webpage containing this answer on the client. From this GitHub website, download the current release of the OpenCore package. Currently this is OpenCore-0.6.7-RELEASE.zip, which by default will become the OpenCore-0 folder in your Downloads folder on the client.

2. Mount the EFI volume: On the client, open a Terminal application window and enter the command given below.

   sudo diskutil mount disk0s1
   

3. Put the shell in the EFI volume: On the client, copy the ~/Downloads/OpenCore-0/X64/EFI/OC/Tools/OpenShell.efi file to the root folder on the EFI volume. Rename this file to shellx64.efi.

4. Put the startup script in the EFI volume: This step is optional, however the script does create useful aliases and environment variables. Also, the display mode is set so the shell uses the entire console window.

   Open this webpage on the client, then save the script given below as an ASCII text file named startup.nsh in the root folder on the EFI volume.

   @echo -off
   mode 128 40
   set -v AppleEnv 7C436110-AB2A-4BBB-A880-FE41995C9F82
   if x%uefishellversion% == x then
       # Startup commands for EFI 1.0 shells
       alias -v cv "ver -s"
       alias -v ush "shellx64.efi -nomap -noversion -delay 0"
       if "x%StartupDelay%" == x then
           set StartupDelay 0
       endif
       cls
   else
       # Startup commands for UEFI 2.2 shells
       set -v ShellAlias 0053D9D6-2659-4599-A26B-EF4536E631A9
       set -v SEnv 158DEF5A-F656-419C-B027-7A3192C079D2
       alias -v csrutil "setvar csr-active-config -nv -rt -bs -guid %AppleEnv%"
       alias -v cv ver
       if "x%ShellOpt%" == x then
           setvar ShellOpt -nv -bs -guid %SEnv% =L"-nomap -noversion -delay 0" =0000
       endif
   endif
   cv
   

5. Restart to firmware: Shutdown the client. On the host, open the Startup Disk pane of Settings for the client. Hold down the option key and select the Restart to firmware… button.

6. Add boot option: From the client firmware menus, select Enter setup>Configure boot options>Add boot option, then select the EFI volume, as shown in the example below.

   

   Next, select the shellx64.efi file. For a description enter UEFI Shell. and for options data enter -nomap -delay 0. The results should appear as shown below.

   

   Next, select Commit changes and exit>Exit the Boot Maintenance Manager. The window should appear as shown below.

   

7. Test the shell: Select UEFI Shell to boot to the UEFI shell. When finished, enter exit to return to the Boot Manager. If desired, select Shut down the system.

The UEFI shell provided with the CD-R image file form of rEFInd does show output when involved from the rEFInd Boot Manager. Also, the included UEFI shell does not have the problem with the editor mentioned in the accepted answer.

At the time this answer was written, the most current version of rEFInd was 0.13.1. The rEFInd binary included in both refind-cd-0.13.1.zip and refind-cd-0.13.0.zip failed to work properly when installed in the Big Sur VMware Fusion Player client. The rEFInd binary in refind-cd-0.12.0.zip did work, therefore this version was chosen for use in this answer. All three zip files contain the same UEFI shell binary.

Below are the steps need to boot the UEFI shell.

1. Download the ISO file: From this SourceForge website, download the 0.12.0 release of the CD-R image file form of rEFInd to the host. Currently, this is refind-cd-0.12.0.zip, which by default will become the refind-cd-0.12.0.iso file in your Downloads folder on the host.

2. Put the media in the optical drive: If the client is running Big Sur and has media in the virtual optical drive, then instruct the client to eject the media. On the host, place the refind-cd-0.12.0.iso file in the virtual optical drive of the client virtual machine.

3. Boot from the optical drive: On the host, open the Startup Disk pane of Settings for the client. Highlight the DVD icon with the label CD/DVD. Startup the client. If the client is already booed to Big Sur, then instruct Big Sur to restart. The virtual machine will boot rEFInd.

4. Boot the UEFI shell: If necessary, before the timer expires, highlight the console icon labeled Start EFI Shell, as shown below.

   

   If necessary, press the return key to boot the UEFI shell.

Using a startup.nsh File

The accepted answer included a startup.nsh file. This file is optional, however the script does create useful aliases and environment variables. Also, the display mode is set so the shell uses the entire console window. Below are the steps to install this file.

1. Mount the EFI volume: See step 2 in the accepted answer.

2. Put the shell in the EFI volume: See step 4 in the accepted answer.

3. Eject the EFI volume: On the client, enter the command given below in the Terminal application window.

   diskutil unmount disk0s1
   

Moving rEFInd to the EFI volume

The rEFInd has an option for copying itself from the optical drive to the EFI volume. This option is selected in the image below. Copying allows rEFInd to operate without the use of the optical drive. However, this option does not copy UEFI shell file.

If you copy rEFInd from the optical drive to the EFI volume, then you should take the following steps before removing rEFInd from the optical drive. These steps will copy the UEFI shell file to the EFI volume.

1. Boot to the UEFI Shell.

2. Enter the command below to verify the EFI volume is file system mapped to fs0. If correct, then label will be EFI, otherwise try vol FS1, vol FS2, vol FS3, ....

   vol FS0
   

3. Enter the command below to get file system mapping for the optical drive.

   map -t cd
   

4. Assuming the EFI volume is mapped to FS0 and the optical drive is the mapped to FS7, then enter the command below. If you have a different filesystem mapping, then make the appropriate substitutions.

   cp FS7:\EFI\tools\shellx64.efi FS0:\
   

Below is an example.

Shell> vol FS0
Volume EFI (rw)
206472192 bytes total disk space
204619776 bytes available on disk
512 bytes in each allocation unit
Shell> map -t cd
Mapping table
      FS7: Alias(s):CD0b0a0:;BLK10:
          PciRoot(0x0)/Pci(0x11,0x0)/Pci(0x4,0x0)/Sata(0x1,0x0,0x0)/CDROM(0x0)
Shell> cp FS7:\EFI\tools\shellx64.efi FS0:\
Copying FS7:\EFI\tools\shellx64.efi -> FS0:\shellx64.efi
- [ok]
Shell>