Moving VM to external SSD causes disk errors

[ccalabro]

Hi all,

I can create a win/linux/osx vm on my local drive and works no problem.  Take that vm and move it to an external SSD and only the osx vm will work without issue.  Both the Windows or Linux vm's crash, wont load, or have disk errors.

The SSD is fast and stable.  It happens immediately after the move which is curious.  Even more curious is that any macOS vm's I create work fine regardless.

Can anyone please give me a tip in what i am missing. I dont believe its a hardware/file corruption issue.

Any assistance appreciated.

(Sonoma b3 if that makes any difference)

[Technogeezer]

Please define "crash, won't load or have disk errors". Some exact error messages would be helpful.

What Mac platform are you using?

Is the SSD a USB device, or a Thunderbolt device?

How did you move those VMs to the external SSD? Did you move them with the Finder or some other mechanism?

Do you still have the original VMs on your local drive? Or have a backup of those VMs on another drive that you know are OK (not Time Machine!). If you do, repeating the move (or restoring from your backup copy) might be of interest, but you should also verify that the files copied correctly by comparing the hashes of all the files in the VM's bundle.

You can't rule out a hardware issue, file corruption, or an outright bug in Apple's beta. Does this work properly with macOS Ventura on the same hardware?

I hope this is not a Mac that you are depending on for anything, that you have a backup copy of your VMs, and are prepared to revert back to Ventura if necessary.

[ColoradoMarmot · Accepted solution]

Let me add one more question - what format is the external drive?  If it's not APFS, reformat it that way and then try again.

[ccalabro]

SSD is exfat

[ccalabro]

Thanks for the reply. I will get the proper errors, I can only see them in the linux vm’s windows just goes to system repair screeen the fails to boot.

i have the original vm’s on the Mac system drive they work fine. I am just testing them so nothing is critical. 
external drive is usb3.2 ssd in exfat format.

ill collect some more info on the errors.

[Technogeezer · Accepted solution]

Running a VM on ExFAT is a big red flag.

Fusion expects a POSIX compliant file system, and ExFAT formatted disks do not support full POSIX operations. It's very likely that's your problem. ExFAT are good for transfer but not for operation of a VM. And the macOS implementation is not as robust as HFS+ or APFS.

Try that SSD formatted as HFS+ or APFS and see if the symptoms change.

[ccalabro]

exFat was the issue.

made SSD APFS partition and the vm's work flawlessly from there.

Thanks for the assistance everyone, greatly appreciated.

[ColoradoMarmot]

Glad it worked out!