Introduction

It’s not that difficult to install a macOS guest VM on a macOS host using VMware Fusion and personal (non-enterprise) licenses for VMware Fusion are now cost-free. But here are the actual steps.

Get the installer

Method 1

There’s a way built into macOS to get the installer using the softwareupdate --fetch-full-installer command in Applications > Utilities > Terminal.

It will look like this when in progress:

softwareupdate --fetch-full-installer
Scanning for installer
Installing: 19.0%

Once the download is complete, it will stop with the “installing” percentage:

softwareupdate --fetch-full-installer
Scanning for installer
Install finished successfully

Don’t be alarmed by the term Installing. When you fetch the full installer “installing” just means downloading. Nothing will actually be installed.

Method 2

Another way to fetch the macOS installer is to use the installinstallmacos.py script:

sudo installinstallmacos.py

One advantage of using this script is you have the option to pick slightly older installers, if you want to test those instead:

# ProductID Version Build Post Date Title
1 001-15219 10.15.5 19F2200 2020-06-15 macOS Catalina
2 001-68446 10.15.7 19H15 2020-11-11 macOS Catalina
3 071-00696 11.4 20F71 2021-06-02 macOS Big Sur
4 001-36801 10.15.6 19G2021 2020-08-12 macOS Catalina
5 001-04366 10.15.4 19E2269 2020-05-04 macOS Catalina
6 071-97382 11.6 20G165 2021-09-17 macOS Big Sur
7 061-86291 10.15.3 19D2064 2020-03-23 macOS Catalina
8 041-91758 10.13.6 17G66 2019-10-19 macOS High Sierra
9 041-88800 10.14.4 18E2034 2019-10-23 macOS Mojave
10 061-26589 10.14.6 18G103 2019-10-14 macOS Mojave
11 001-51042 10.15.7 19H2 2020-09-24 macOS Catalina
12 071-71342 11.5 20G71 2021-07-21 macOS Big Sur
13 071-72781 11.5.1 20G80 2021-07-26 macOS Big Sur
14 001-57224 10.15.7 19H4 2020-10-27 macOS Catalina
15 041-90855 10.13.5 17F66a 2019-10-23 Install macOS High Sierra Beta
16 061-26578 10.14.5 18F2059 2019-10-14 macOS Mojave
17 071-78704 11.5.2 20G95 2021-08-18 macOS Big Sur
18 001-36735 10.15.6 19G2006 2020-08-06 macOS Catalina

Choose a product to download (1-18):

Creating the VM

Once you launch up VMware Fusion, you’ll get a prompt asking you for a disc or image.

Find the Install macOS Big Sur.app installer. If you used softwareupdate, that should appear in your Applications folder. If you used installinstallmacos.py, you’ll have to mount (by double-clicking) the disk image you downloaded to find the installer inside.

Then, drag it to Install from disc or image.

Click through the next steps.

Click the play button to start up the VM and boot into macOS’s recovery mode.

Select your language.

Then, launch up Disk Utility.

Initially, it will focus on macOS Base System. That’s not what you want to focus on here.

Instead, you should click on Macintosh HD, and then click the Erase button.

Switch from Mac OS Extended…

… to APFS.

Once you’re done with Disk Utility, launch up Install macOS Big Sur.

Click through the installer wizard.

Once the installer finishes, you should be at the Setup Assistant, and you can set up your VM just as you would a factory reset Mac.

Why not install from the recovery partition?

In theory, VMware Fusion has an option to install from your host Mac’s recovery partition instead of from an installer. If you can get it to work, great! But this is what I’ve seen when trying to use that option…

It appears to work…

But, then, when it comes to actually launching up the virtual machine, a weird boot loop happens.