VM reconfiguration fails when vGPU present with more than 128 vCPUs are active

Products

• VMware vSphere ESXi 8.0

Issue/Introduction

If you add more than 128 vCPUs to a VM with a vGPU, you cannot manage the configuration from the vSphere Client. 

Environment

ESXi 8.0

Cause

The issue occurs because input–output memory management unit (IOMMU) support for a vGPU with more than 128 vCPUs is not available.

Resolution

This issue is resolved in VMware ESXi 8.0 Update 3e
Refer to the resolved section on: https://techdocs.broadcom.com/us/en/vmware-cis/vsphere/vsphere/8-0/release-notes/esxi-update-and-patch-release-notes/vsphere-esxi-80u3e-release-notes.html

With the fix, you can manage the vGPU VM configuration from the vSphere Client.

However, the VM might not be able to power on, since IOMMU support is not available. To make sure the reconfiguration succeeds, add the following 2 parameters to the .vmx file : 

pciPassthru.vmiop.allowViommu="TRUE"
and 

pciPassthru.vmiop.enableViommu="TRUE"

 

Ref KB to enable the above settings: https://knowledge.broadcom.com/external/article/313255/vsphere-esxi-80-vgpu-support-for-128+-v.html