06-28-2025 03:34 PM
I'm currently trying to get CML personal (v2.7.2) working on VMware Workstation 17 Pro (v17.6.3 build-24583834), and I keep getting an error message that says, "VMware Workstation does not support nested virtualization on this host. Module 'HV' power on failed. Failed to start the virtual machine." I have a Windows 10 x64-based Lenovo laptop with an Intel Core i7-11850H Processor. I've tried.
bcdedit /set hypervisorlaunchtype off
Ensured that my CPU supports virtualization extensions
Disabled Virtualization-based Security (VBS)
Nothing seems to work. Does anyone have a clue what I can do to get CML working
Solved! Go to Solution.
06-29-2025 01:10 PM
This message from VMware Workstation, and its companion message from the CML installer "Virtualized Intel VTx/EPT is not supported on this platform", comes up frequently on the CML-Personal community support site. The root cause is that the VTx extensions enabled in BIOS are not being propagated up from the physical CPU, through Windows, and into WMware so that Workstation's virtual CPUs for the CML VM have VTx support that can be exposed to CML's KVM. Cisco's CML team has has put together a procedure that is a superset of the steps you have taken to expose the VTx extensions to VMware from Windows. If those steps do not work for you and you have Windows 11 Pro, you might also try running CML on Hyper-V using the steps on the CML github site.
FWIW, you might run with CML 2.8.1 instead of 2.7.2, as it has been out for some time, though it does not address this nested virtualization issue (this is a Microsoft security "feature").
06-28-2025 10:32 PM
= @jollysonan FYI : https://community.broadcom.com/vmware-cloud-foundation/discussion/vmware-workstation-does-not-support-nested-virtualization-on-this-host-module-hv-power-on-failed
M.
06-29-2025 01:10 PM
This message from VMware Workstation, and its companion message from the CML installer "Virtualized Intel VTx/EPT is not supported on this platform", comes up frequently on the CML-Personal community support site. The root cause is that the VTx extensions enabled in BIOS are not being propagated up from the physical CPU, through Windows, and into WMware so that Workstation's virtual CPUs for the CML VM have VTx support that can be exposed to CML's KVM. Cisco's CML team has has put together a procedure that is a superset of the steps you have taken to expose the VTx extensions to VMware from Windows. If those steps do not work for you and you have Windows 11 Pro, you might also try running CML on Hyper-V using the steps on the CML github site.
FWIW, you might run with CML 2.8.1 instead of 2.7.2, as it has been out for some time, though it does not address this nested virtualization issue (this is a Microsoft security "feature").
08-12-2025 03:12 AM
Try GNS3 instead. More stable and less issues.
08-12-2025 06:23 AM - edited 08-12-2025 06:35 AM
Hello, I use both CML modeling labs 2.8.1 and GNS3 Version 2.2.54 . But I have a different setup. I use this hardware minisforum um790 pro and installed proxmox virtual environment on the mini pc. From there you can install vm ware containers: how to setup cml on proxmox/ or cml on proxmox/
I think mini pc's are excellent for CML and GNS3 in combination with proxmox. Installation on laptops/notebook with VMware 17.5 is not something I would recommend. Hyper-V is worthless. Don't use it. The mini pc has 64 Gb DDR5 ram but 32 Gb should be sufficient for most labs.
GNS3 works also very well on proxmox and de herefore mentioned mini pc. how to install gns3 on proxmox or How to set up GNS3 server on Proxmox
I know that is not the answer to your question or problem but maybe it's a good idea to buy a refurbished of second hand minisforum pc like I did. Saves a lot of money and no longer annoyances about hardware that is not functioning.
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