WilliamLam.com

Unable to power on vSphere Cluster Services (vCLS) VM in Nested ESXi with no host is compatible with the virtual machine

by // 8 Comments

After deploying a new VMware Cloud Foundation (VCF) Workload Domain using the VCF Holodeck Toolkit, which leverages Nested ESXi, I noticed the vSphere Cluster Services (vCLS) VMs kept failing to power on and threw the following error message:

No host is compatible with the virtual machine


I thought this was quite strange, especially since the vCLS VMs ran fine when the VCF Management Domain was setup.

UPDATE (07/03/2024) - The reason for the vCLS error is actually due to the miss-configuration of the Nested ESXi VM created by VCF Holodeck Toolkit, please see this blog post for an easier fix.

Looking at the vmware.log for the vCLS VM, I quickly found the issue where the VM expects to have the MWAIT CPU instruction exposed:

2024-03-19T16:35:35.736Z In(05)+ vmx - Power on failure messages: Feature 'cpuid.mwait' was 0, but must be 0x1.
2024-03-19T16:35:35.736Z In(05)+ vmx - Module 'FeatureCompatLate' power on failed.
2024-03-19T16:35:35.736Z In(05)+ vmx - Failed to start the virtual machine.

I figure I was probably not the first person to run into this and asked Ben Sier, who works on Holodeck and indeed he ran into this before. It looks like with newer vSphere releases, it expects to configure Per-VM EVC but the vCLS VM may not function properly within a Nested ESXI environment. Luckily, Ben has a workaround that we can quickly use.

[Read more...]

vSphere 8.0 Update 1c resolves Windows VBS performance & Hyper-V Generation 2 Nested VM running on AMD CPU

by // 1 Comment

vSphere 8.0 Update 1c was just released and one of the resolved issues mentioned in the ESXi release notes is the following:

Nested virtual machines on AMD CPUs with operational systems such as Windows with virtualization-based security (VBS) might experience performance degradation, timeouts, or unresponsiveness due to an issue with the virtualization of AMD's Rapid Virtualization Indexing (RVI), also known as Nested Page Tables (NPT).

UPDATE (10/11/23) - This is also resolved in the ESXi 7.0 Update 3o release

There are two scenarios in which this fix resolves:

  1. Running Windows Server VM with a Hyper-V enabled Generation 2 VM (Nested Virtualization) on AMD CPU
  2. Running Windows Server VM with VBS Enabled (Non-Nested VM) on AMD CPU

[Read more...]

Refresher on Nested ESXi Networking Requirements

by // 11 Comments

Using Nested Virtualization and specifically Nested ESXi, which is running ESXi inside of a VM, has become so automatic and second nature for me and many in the VMware community, that I sometimes forget we still have brand new users who are experiencing ESXi for the very first time.

Nested ESXi is an extremely powerful capability for so many different use cases from development, testing and general learning purposes. Before jumping in and deploying your Nested ESXi environment, which I highly recommend using my Nested ESXi Virtual Appliances, you need to make sure that you have proper networking setup or you will run into all sorts of strange issues. For all VMware Nested Virtualization resources, tips and tricks, you will definitely want to bookmark this page HERE.

Disclaimer: Nested Nested ESXi is not officially supported by VMware and Nested Virtualization is only supported under limited scenarios. For more details, please refer to this VMware KB 2009916.

[Read more...]