Cannot install VMs on VirtualBox

samiam

Active Member
Oct 8, 2013
17
2
41
I have the latest stable VirtualBox running on the latest stable Windows 11. I enabled Nested VT-x/AMD-V and gave it lots of memory, lots of pre-assigned storage. I can install the latest stable Proxmox (7.4.1) no problem. However, when I try setup a KVM VM on Proxmox it crashes Proxmox a little ways into the install from ISO on the VM, requiring me to restart it on Virtualbox. The Virtualbox log file doesn't give any clues.

I google around and found some others having similar problems in the past on older versions of Proxmox and Virtualbox but no resolution other than to update to the latest version of everything, which I am already doing. The VM I am trying to install on Proxmox is Linux, not Windows. I've fiddled around with various settings on Virtualbox to no avail. I suspect it's related to Virtualbox Nested VT-x/AMD-v misbehaving but there aren't any settings to change there. It's either enabled or disabled and Proxmox won't work when it's disabled. It is definitely working as designed because can create the Proxmox VM with KVM hardware virtualization enabled and it is noticeably faster than when it's disabled, which is far too slow to do anything with. It's always a few minutes into the install from ISO on the VM that it crashes everything.

I run lots of other VMs on VirtualBox and don't have problems with any of them crashing. Including other VMs that also require Nested VT-x such as SolusVM 2. I have HyperV fully disabled on Windows 11 so that is not interfering.
 
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I managed to get a Linux OS to fully install inside a KVM VM on Proxmox just once by setting Virtualbox Network to "Host-only Adapter". Setting it to "Bridged Adapter" makes it fail early in the VM install process. So it seems to be related to Virtualbox network adapters. It still crashes but not as often or as quickly when using "Host-only Adapter".
 
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Are you installing a VM into your proxmox(hypervisor), which is already inside a hypervisor(VBox)?
I am no expert, and this is not a criticism, but am curious as to why - especially on top of "stable" w11?
I am doing testing and development work. I don't need to use it for production just yet so I am not ready to spend money on hardware in a datacenter. I need to do it on my laptop while remaining mobile so installing Proxmox on old hardware in my basement is not really an option either.
 
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Have you also tried changing the adaptor types?
View attachment 49274
I tried changed that and it still crashed.

I have downloaded some premade cloud templates and created clones to get around the crashing and am able to use the Bridged Adapter now by doing that. It still crashes once in awhile when booting the cloned VMs but it's good enough for development and testing work for now.

I just need to have some VMs and templates installed while I do some testing and coding for the API. It's obviously not stable enough to do much more than that and I don't expect that to change anytime soon.
 
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This should be working without any hassle. I used your setup for the exact same reason. I do though experience some instabilities since I upgraded to VirtualBox v7. Maybe the late VirtualBox v6 could be an option.
 
This should be working without any hassle. I used your setup for the exact same reason. I do though experience some instabilities since I upgraded to VirtualBox v7. Maybe the late VirtualBox v6 could be an option.
That is good to know. I need to do my development and testing on the latest released version so using v6 is not really an option. I just updated to the 5.15.104-1-pve kernel and it's still crashing.
 
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