Catalina Back To Mojave

This exercise was to get a running MacOS Catalina VM instance running on VMware. I first wrote this for Catalina Beta but afte rthe official release, a couple things changed. So now it is how to install Catalina on ESXi 6.7. I am using a 2013 Mac Pro with VMWare 6.7 U2 installed. I have High Sierra and Mojave VMs running on the host. Downgrade Catalina to Mojave. If you’ve installed macOS Catalina and run into problems with some of your apps, or you’ve just decided that you don’t like it as much as Mojave, the good news is that you can downgrade back to the previous version of macOS. The bad news is that it’s a lengthy process with several steps.

on VMware ESXi 6.7 U3 P02

** UPDATE 12/03/2020**

This now installs natively on ESXi 6.7 Update 3 Patch 02 - 202004002

I followed my same procedure below after downloading Catalina and Big Sur.

** I increased the image sise to 13GB as Some Catalina versions were greater than 8GB and Big Sur is 12.9GB

hdiutil create -o /tmp/catalina -size 13000m -layout SPUD -fs HFS+J

hdiutil attach /tmp/catalina.dmg -noverify -mountpoint /Volumes/install_build

/Applications/Install macOS Catalina.app/Contents/Resources/createinstallmedia --volume /Volumes/install_build

hdiutil convert /tmp/catalina.dmg -format UDTO -o ~/Downloads/catalina

mv ~/Downloads/catalina.cdr ~/Downloads/catalina.iso

Next, I copy the ISO to a external system (my desktop) an a network drive where I will install from.

In VMware (I am using vCenter)

Name it, I use macos-catalina

Pick a folder, Pick a Server/resource Pool and Pick Storage

For Compatibility, click the dropdown and select ESXi 6.7 Update 2 and later

For Select OS, click the Gueast OS Family drop down and select Other

For Guest OS Version, click the dropdown and select Apple macOS 10.14 (64-bit)

Under the datastore, I choose Disk Provisioning Thin Provision

Finish and save the VM

To install, I open a remote console on the VM

Select VMRC - > Removable Devices -> CD/DVD Drive1 -> Connect to Disk Image File (ISO)

In the OS boot menu, select SATA CD/DVROM, then boot to the installer

Select the VMware Virtual Disk

Give the disk a name

Start the macOS installer and complete the install steps. This takes about 45 minutes total.

Once installed, disconnect the ISO from the console client.

Reboot one last time to make sure it still boots OK.

** UPDATE 04/15/2020**
Seems you need to start at Mojave to be able to download the full Catalina package from the App Store. I started from Mojave so I never ran into the issues found in the comments. Check the comments for what Adam had to say...
** UPDATE 10/17/2019**
After applying the first update, the VM was rendered un-bootable again. That is the same crash that is originally experienced. SEE Boot Work Around at the bottom.
This exercise was to get a running MacOS Catalina VM instance running on VMware. I first wrote this for Catalina Beta but afte rthe official release, a couple things changed. So now it is how to install Catalina on ESXi 6.7.
I am using a 2013 Mac Pro with VMWare 6.7 U2 installed. I have High Sierra and Mojave VMs running on the host. Running VMs on VMware is something I've done for a few years.

A lot has changed in Catalina. Admittedly, I am not a MacOS expert. I'm not particularly good a Mac user either. So, I can't speak to the changes only that it is not currently (Oct 1, 2019) frienld to install on VMware ESXi. Catalina runs fine once you get a working VM though.

The MacOS Part

As of this writing (10/10/2019), You cannot upgrade and existing VM running High Sierra or Mojave. At least, I could not successfully upgrade and boot to Catalina.

If at first You Don't Succeed...

Note: You need to start at Mojave to upgrade to download the fill Catalina package.
I started with trying to upgrade a Mojave VM to Catalina. I just downloaded Catalina from the Apple Store (Search: macos catalina).

I followed the prompts and downloaded the Catalina installation image. I ran though the installation process which seemed to go pretty well. That is until it booted from the upgraded image. Then, it crashed. You can't see the crash, you just has an frozen Apple logo.

To see what is happening, reboot the VM and hold down the Windows Key + v for Verbose mode and see the boot attempt and the kernel panic. Changing VMware setting had no affect. After a couple hours, I gave up.

Try Something Else... And It Worked!

My next tack was to boot from a Catalina ISO. First, I had to create one. I'd done this before on Mojave so it wasn't all unfamiliar. The steps are below. I am not sure where they came from.

First, I had to boot back to Mojave. I had found by rebooting the VM to the Boot Manager settings (you can set this in the VM settings or press escape before the OS loads in a VM console) and Selecting the EFI VMware Virtual SATA Hard Drive (0,0) option (not Mac OS X), that boots to my original Mojave image.
To start from scratch on a Mojave instance, download Catalina from the app store (Search: macos catalina). Just don't run the installer. You need the app image to create the ISO.

Once Mojave loaded, to build the ISO file, I start by making the virtual disk:

hdiutil create -o /tmp/catalina -size 13000m -layout SPUD -fs HFS+J

Then, I mount it to I can copy the installer to it

hdiutil attach /tmp/catalina.dmg -noverify -mountpoint /Volumes/install_build

Now I copy the installer to the mounted image

sudo /Applications/Install macOS Catalina.app/Contents/Resources/createinstallmedia --volume /Volumes/install_build

The image is automatically mounted and is on your desktop. Select it and un-mount the image.

Now convert the image to an ISO file. You can put the file anywhere but I used ~/Downloads for simplicity

hdiutil convert /tmp/catalina.dmg -format UDTO -o ~/Downloads/catalina

Now rename the file from catalina.cdr to catalina.iso

mv ~/Downloads/catalina.cdr ~/Downloads/catalina.iso

You can delete /tmp/catalina.dmg.

Copy the ISO to your PC or where ever you want to attach it to the VM via a console session. I use WinSCP to copy to my PC.

The VMware Part

I created a blank VM with the following settings:
These are important. Just follow my lead here.

Guest OS Version: Apple macOS 10.14 64-bit

4GB Memory

The rest is default

Once the VM is saved, edit the settings and change to
Guest OS: Windows

Guest OS Version: Windows 10 64-bit

Changed to Windows 10

Next...
Open a Remote Console (VMRC)

Click VMRC --> Removeable Devices --> CD/DVD --> Connect to Disk Image File

Navigate to the catalina.iso file you saved where ever, Click Open

Attach ISO

Now ALT+CTRL+Insert in the VM to reboot it. It will boot from the ISO automatically. If not select the SATA CDROM frm the EFI menu. Note, sometimes it took several reboots for it to successfully boot from the ISO. usually, just one.

Once the installer image loads, use the disk tool to erase the VMware virtual disk (100GB in my case)

Use the default erase options (Note: Your keyboard doesn't work so just accept 'Untitled')

Next, choose to install MacOS

Follow the install steps and install Catalina

Once the install finishes, it will reboot to the OS. Make sure you detach the ISO so you don't boot to the installer again.
Reset the VM
The VM should boot to the image and continue installing Catalina. When it finishes (10 or so minutes) it will reboot.

After the reboot, it will freeze on the blank Apple logo or unsuccessfully load MacOS X. Don't fret.. We're OK.
Power off the VM

Edit the VM setting and change the OS values.

Guest OS Version: Apple macOS 10.14 64-bit

Power on the VM and it will boot to and load Catalina.

Once you go through the setup steps and Catalina is ready to go.

Good luck on your adventure!

Added 10/17/2019

After applying the update, the VM was no longer booting. Same cast at boot with the Apple Logo and no progress.

the work around is to change the boot order in EFI boot settings to boot to SATA Hard Drive 0.0

You need to enter EFI boot configuration for the VM. You can hit escape a the VMware logo or go to the VM settings and set to boor to EFI next boot. Boot/reboot to get the EFI menu

Enter Setup
Configure Boot Options
Change Boot Order
Press Enter then change the boot order in the pop up window using + and - keys. Press Escape when done editing.
Move EFI Virtual SATA Hard Drive (0.0) to the Top

Uninstall Catalina Back To Mojave

You can see I change the overall boot order to:
Hard Drive
CDROM
Mac OS X

Press Enter to Commit changes and exit

macOS Big Sur elevates the most advanced desktop operating system in the world to a new level of power and beauty. Experience Mac to the fullest with a refined new design. Enjoy the biggest Safari update ever. Discover new features for Maps and Messages. And get even more transparency around your privacy.

Check compatibility

macOS Big Sur is compatible with these computers:

MacBook introduced in 2015 or later
MacBook Air introduced in 2013 or later
MacBook Pro introduced in late 2013 or later
Mac mini introduced in 2014 or later
iMac introduced in 2014 or later
iMac Pro
Mac Pro introduced in 2013 or later
View the complete list of compatible computers.

If upgrading from macOS Sierra or later, macOS Big Sur requires 35.5GB of available storage to upgrade. If upgrading from an earlier release, macOS Big Sur requires up to 44.5GB of available storage. To upgrade from OS X Mountain Lion, first upgrade to OS X El Capitan, then upgrade to macOS Big Sur.

Make a backup

Before installing any upgrade, it’s a good idea to back up your Mac. Time Machine makes it simple, and other backup methods are also available. Learn how to back up your Mac.

Get connected

It takes time to download and install macOS, so make sure that you have a reliable Internet connection. If you're using a Mac notebook computer, plug it into AC power.

Download macOS Big Sur

If you're using macOS Mojave or later, get macOS Big Sur via Software Update: Choose Apple menu  > System Preferences, then click Software Update.

Or use this link to open the macOS Big Sur page on the App Store: Get macOS Big Sur. Then click the Get button or iCloud download icon.

Going From Catalina Back To Mojave 2019

Begin installation

After downloading, the installer opens automatically.

Click Continue and follow the onscreen instructions. You might find it easiest to begin installation in the evening so that it can complete overnight, if needed.

If the installer asks for permission to install a helper tool, enter the administrator name and password that you use to log in to your Mac, then click Add Helper.

Allow installation to complete

Please allow installation to complete without putting your Mac to sleep or closing its lid. Your Mac might restart, show a progress bar, or show a blank screen several times as it installs both macOS and related updates to your Mac firmware.

Uninstall Catalina Back To Mojave

Stay up to date

After installing macOS Big Sur, you will be notified when updates to macOS Big Sur are available. You can also use Software Update to check for updates: Choose Apple menu  > System Preferences, then click Software Update.

Or get macOS Big Sur automatically

If you're using OS X El Capitan v10.11.5 or later and your App Store preferences or Software Update preferences are set to download new updates when available, macOS Big Sur will download conveniently in the background, making it even easier to upgrade. A notification will inform you when macOS Big Sur is ready to be installed. Click Install to get started, or dismiss the notification to install later. When you're ready to install, just open the file named Install macOS Big Sur from your Applications folder.

Learn more

If the installer shows a list of apps that are not optimized for your Mac, learn about 32-bit app compatibility, then choose whether to proceed with the installation.
For the strongest security and latest features, upgrade to macOS Big Sur. If you have hardware or software that isn't compatible with Big Sur, you might be able to install an earlier macOS.
You can also use macOS Recovery to reinstall the macOS you're using now, upgrade to the latest compatible macOS, or install the macOS that came with your Mac.