Best practices for upgrading virtual machine hardware compatibility when OEM drivers are being used on the guest OS

Products

• VMware vSphere ESXi

Issue/Introduction

• When upgrading virtual hardware compatibility to match a newer host version, concerns often arise regarding the risk of replacing OEM drivers within the guest operating system.
• Upgrading hardware compatibility is recommended to enable the virtual machine (VM) to utilize the latest features and performance enhancements of the host.
• The risk is low because VMware Tools provides the necessary drivers for the virtual hardware.
• However, since the hardware interface presented to the guest OS changes, the recommendation is to follow the standard procedure described in this KB, to ensure a safe transition when modifying the hardware interface presented to the guest OS.

Environment

VMware vSphere ESXi

Resolution

Note: If the hardware upgrade is performed without updating VMware Tools first, the Guest OS may fail to recognize the "new" hardware, resulting in a loss of network connectivity or a boot failure.

The following is a standard procedure to safely upgrade virtual hardware compatibility: (Please note to consult with the KBs in the additional information section for the actual detailed instruction steps)

1. Update VMware Tools first: Always ensure VMware Tools is at the latest supported version for your Guest OS before changing hardware compatibility. This ensures the guest has the drivers required for the new hardware version.
2. Take a Snapshot: Power off the virtual machine and capture a snapshot. This provides an immediate rollback point if the Guest OS encounters stability issues after the upgrade.
3. Perform the Upgrade:
   • Keep the VM powered off.
   • Select the option to upgrade hardware compatibility to the desired version.
4. Power On and Verify:
   • Power on the VM and log in to the guest OS.
   • Open Device Manager to ensure all drivers (specifically Network and Storage controllers) are initialized and functioning correctly.

Additional Information

Consult with the following KBs for detailed instructions and compatibility mapping, before proceeding with the hardware upgrade:

• Upgrading a virtual machine to the latest hardware version: KB 315390

• Virtual machine hardware versions and compatibility: KB 312100