VMs cannot see bootdisk after Proxmox Upgrade - 6.4 -> 7.0-11

[Alpha12962]

Could anyone assist me as to understanding what has happened here?
All virtual machines without physical boot media just hang on booting from hard disk...
How do I proceed in fixing this?
Any help is much appreciated.

VM 1, Example 1/2:





VM 2, Example 1:

 

[Alpha12962]

I've got my VMs working again.

Setting the Machine version to 5.2 lets run without any additional configuration required.

I'm curious to know why 6.0 completely breaks my storage.

 

[polarwinkel]

I had the same problem ans solved it by using an older kernel.
But this seems not to be a not-found-hd-problem, since I had the problem also when booting from an iso: it got stuck after a few seconds. And all VMs were broken, Linux and Windows, while LXC-Containers worked fine.

It is working on kernel 5.3.18-3-pve, and did fail on 5.4.140-1-pve.

There was a longer thread also describing this problem earlier this year on Proxmox 6, but I can't find it anymore, so I post it here.
It seemed to happen only on systems using local-zfs.
In my case on a Ryzen Threadripper TR 2970WX WOF on a MSI X399 SLI PLUS-Board