Fusion 13 / macOS 12 : "Unable to create the installation medium"

[pkeller]

I'm trying to create a VM with macOS 12.6.1 under Fusion 13. I downloaded the "Install macOS Monterey" application, drag it into the new-VM dialog, tell it that it's macOS 12, save the machine, ... and then I get the dreaded "Unable to create the installation medium" message.

None of the suggested fixes for the same problem in previous versions of Fusion seem to work for me. In particular, I tried moving the installer out of the Applications folder onto my desktop, and I verified that the installation disk image was not already mounted.

Does anyone have any other suggestions?

[Technogeezer]

I'm seeing this same behavior, but don't have an idea on what's going wrong either. My initial thought would be to create bootable macOS USB media from the installer using Apple's instructions here https://support.apple.com/en-us/HT201372

 

[pkeller]

Thanks for confirming the problem. I'm now working with VMware's Tech Support on this; I'll post our findings as soon as there are some.

I pursued exactly the same route as you're suggesting, except, since I didn't have a USB key that was big enough, I copied the installer to a disk image. I got that to work, but the VM was not able to boot off it. So I might just have to go out and buy a bigger USB stick (16 GB minimum), and do exactly what you're suggesting... unless you have the material to do that experiment?

[Technogeezer]

Try using this open-source script that creates a bootable disk image as well as an ISO file. 

https://github.com/rtrouton/create_macos_vm_install_dmg

I just used it and I asked it to create the ISO in addition to the .dmg. I created a custom virtual machine for macOS 12 and attached the ISO to the the CD/DVD drive.

Booted the VM and the ISO booted to recovery. It didn't seem to like NAT networking (couldn't seem to find the Apple servers). I switched to Bridged networking and it's now installing. 

 

[pkeller]

Yes! I'm in the process of installing, too. I see that the script uses a map with 3 partitions; I didn't do that and I suspect that's why my .dmg didn't boot. Thanks for the workaround!

I will report this to VMware Tech Support, and report back if they find out why their regular installation process doesn't work.

[pkeller]

Just to close the loop on this question: I verified that you can also boot off the .dmg generated by the shell script.

[provingGround]

I'm surprised this problem still exists, but can confirm this solution still works as of this post. TY

[ColoradoMarmot]

MacOS Guest support is being depreciated (especially on Intel), so I wouldn't expect a fix.

[SvenGus]

… And still - a script that could probably be fixed in less than an hour - not fixed in the first 2023 Fusion Tech Preview: while in Parallels any macOS install media can be created directly from within the app and one can also have a perfectly working macOS 14 Sonoma VM, with graphics acceleration and everything else working perfectly. Well, Parallels 10-Fusion 0 (on this particular front, of course, not in general)…

[Technogeezer]

Well, maybe not an hour but certainly should not be a big effort for someone familiar (or takes the time) to research how to build the media. 

VMware seems to be stuck in the mindset that everything has to be a derivative of or compatible with vSphere.  That attitude blinds VMware from turning Fusion into the "real" macOS product it could be. Parallels is under no such corporate inertia.

[ColoradoMarmot]

VMWare has depreciated support for MacOS guests, so they're not going to build anything for them.

It's a lot more than an hour - coding, testing, documentation, etc.  I'd much rather have them working on something that's supported going forward (like shared folders for windows) than something for a guest OS thats DOA.

[Technogeezer]

 - both can be true at the same time. VMware abandoned macOS virtualization because they're skating to where they believe the puck is going to be, not where it is.. 

In general, though. VMware leaves a lot of good Mac ideas on the table because of their corporate inertia. I'm surprised in a way that Apple Silicon platforms have gotten as much attention has they have. It's not an insignificant amount of work and corporate strong-arming to get Windows 11 ARM support for example when arm64 is an orphaned red-headed stepchild in the eyes of the x64-centric VMware monolith. 

[RDPetruska]

 They have also left a lot of good Windows ideas on the table as they keep crippling Workstation year after year as well.  TONS of cool/useful features have gone by the wayside over the years as they appear to just chase the big corporate customers with vSphere and cloud and all that other crap.  I still cannot believe any serious company is allowing their data to get stored "up in the cloud"... way too many security risks there.  Of course, I work in an industry where security is critical, so my view may be skewed perhaps - but I still fail to comprehend why so many companies ignore or overlook how insecure their data is, doing that.

[Technogeezer]

"show me the money" comes to mind  . Companies that don't embrace the cloud are doomed to irrelevancy in the broader marketplace. 

You are correct that many companies have jumped on the cloud bandwagon with a promise of lower costs and expectation that "the cloud provider will take care of all the details". Which, as you and I know, is not necessarily true. The need to secure and protect one's data does not go away just because the data is "in the cloud" aka the computer you don't own.

It's amusing to see the reaction in the faces of CFOs when they see the bill for cloud services thinking they were going to save all that money. Or the reaction of business owners and CIOs when data's been lost, compromised, or the series goes down when in the cloud.

The more things change, the more they stay the same...

[SvenGus]

Curiously, in the Fusion 2023 Tech Preview, macOS 14 is present as a guest option (but the install media creation script, as said before, doesn’t work): so, maybe there’s still hope for some macOS guest support, at least on Apple Silicon, who knows…

[ColoradoMarmot]

They are supposed to be cleaning up that list - there's a disconnect between it and tool support.

The tools are definitely depreciated.  But they still work on Intel.  I wouldn't count on anything for ARM because the tools are built common across all VMWare products, and I doubt the Fusion team will take on building custom tools for a niche use case on a niche product (especially when the windows tools still have gaps).

As for the OT cloud thread, I do cybersecurity for a living.  Cloud computing can be made just as secure as on-prem (and in many many cases, it's more-so, especially for smaller orgs).

[msschmitt]

Instructions for manually creating a macOS VM from an installer, without using scripts:

1. In terminal create an empty disk image: 

   hdiutil create -o "Installer.dmg" -size 15g -layout SPUD -fs "HFS+J"

2. Open the .dmg to mount it. It probably will mount as "untitled".
3. Follow the instructions at https://support.apple.com/en-us/HT201372 to create installer media, aiming it at /Volumes/untitiled.
4. Eject the new installer. Also use Disk Utility to eject the Shared Support image; there's a bug in macOS installers that leaves it mounted.
5. In Fusion, create a new VM.
6. At "Select the Installation Method", drag the .dmg file to "Install from disc or image".
7. Continue through the New VM dialogs as normal.

The VM will be set to boot from the installer disk image, attached to the virtual CD ROM drive. It doesn't matter where the installer is; there's no requirement that it be copied into the VM's folder.

[Snow_Leopard]

Excellent.

If I may, I would suggest some minor cosmetic details to avoid the curse of knowledge (given that mere mortals are not as familiar with the subtleties as you are).

For instance, please use the fully qualified name "Installer.dmg" instead of simply "the .dmg".

Well done. Your procedure worked perfectly.

Thank you.