VMware Tools version 12.4.5.0 (or similar minor builds within the 12.4.x series) experience intermittent or consistent network connectivity drops

Products

• VMware vSphere ESXi

Issue/Introduction

VMware Tools are a set of utilities that enhance the performance of the virtual machine's guest operating system and improve the management of the VM. They include crucial drivers, such as the Vmxnet3 network adapter driver, which is essential for optimal network performance and stability in a virtualized environment. This specific network connectivity issue has been identified as a bug within VMware Tools version 12.4.5.0.

This leads to:

• Temporary loss of network access for applications and services running within the VM.
• Inconsistent network performance or packet loss.
• Appears as an issue with the virtual network adapter (typically Vmxnet3).

Environment

VMware vSphere ESXi 8.x

Cause

The root cause is a bug or instability within the network components/drivers (primarily the Vmxnet3 driver) packaged with VMware Tools version 12.4.5.0. This defect can lead to:

• Intermittent driver failures.
• Improper handling of network traffic, resulting in packet drops.
• Temporary cessation of network communication, requiring a driver reset or VM restart to restore.

This issue has been addressed by VMware in subsequent versions of VMware Tools.

Resolution

The confirmed fix for this network connectivity issue is to upgrade VMware Tools to a version in the 13.x series (e.g., 13.0.0 or later stable releases). VMware Tools 13.x contains updated and more stable network drivers that resolve the problem.

A. Prerequisites & Best Practices (CRITICAL):

1. Take a Snapshot: Before starting the upgrade, always take a snapshot of the virtual machine. This provides a quick revert point if any issues arise during or after the upgrade.
2. Backup the VM: If possible, perform a full backup of the VM.
3. Schedule Downtime: The upgrade process will require a reboot of the virtual machine for the new drivers to take effect. Plan for appropriate downtime.
4. Verify Compatibility: Ensure the target VMware Tools 13.x version is compatible with your specific ESXi host version and the guest operating system. Consult the VMware Compatibility Guide (VCG).
5. Test in Non-Production (if applicable): If you have a test or development environment, it is highly recommended to perform the upgrade there first to validate the process and functionality.

B. Step-by-Step Upgrade Procedure:

1. Initiate Upgrade from vSphere Client:

   • In vCenter Server, navigate to Hosts and Clusters.
   • Right-click on the affected Virtual Machine.
   • Select Guest OS > Install/Upgrade VMware Tools.
   • Choose "Interactive Tools Upgrade" (or "Automatic" if your environment allows for unattended upgrades).
   • This action mounts the VMware Tools installer ISO to the VM's virtual CD-ROM drive.

2. Run Installer Inside the Guest OS:

   • For Windows VMs:
     • Open "This PC" or "My Computer."
     • Open the virtual CD-ROM drive (usually labeled "VMware Tools").
     • Run setup.exe (for 32-bit Windows) or setup64.exe (for 64-bit Windows).
     • Follow the on-screen prompts. Choose the "Typical" or "Complete" installation option.
   • For Linux VMs:
     • Mount the virtual CD-ROM (e.g., mount /dev/cdrom /mnt).
     • Copy the VMwareTools-<version>.tar.gz package from /mnt to a temporary directory (e.g., /tmp).
     • Extract the package: tar -zxvf VMwareTools-<version>.tar.gz
     • Navigate into the extracted directory: cd vmware-tools-distrib
     • Run the installer: sudo ./vmware-install.pl
     • Follow the prompts, accepting default options where appropriate.

3. Reboot the Virtual Machine:

   • After the installer completes, you will be prompted to reboot the VM. This is mandatory for the new network drivers to become active and for the fix to take effect.

Additional Information

For 12.x and lower version this was the fix: https://knowledge.broadcom.com/external/article?legacyId=79185