VMware Tools still synchronizes guest time although timesync status shows disabled

Products

• VMware vSphere ESXi

Issue/Introduction

• The VMware Tools time synchronization status is showing as Disabled when performing the following command in Windows PowerShell:
  
  C:\Program Files\VMware\VMware Tools\VMwareToolboxCmd.exe timesync status
  
  
• However, Windows Event Logs still show entries indicating that the system time has been changed by VMware Tools：
  
  The system time has changed to [YYYY-MM-DDTHH:MM:SS] from [YYYY-MM-DDTHH:MM:SS].

Change Reason: An application or system component changed the time.
Process: ‘\<Path>\Program Files\VMware\VMware Tools\vmtoolsd.exe’ (PID ####).

Environment

VMware vSphere ESXi 8.x

Cause

VMware Tools can perform two types of time corrections: periodic time sync and one-off time sync. The CLI command only reports the status of periodic time synchronization. 

If one-off time sync is enabled, the guest operating system clock is synchronized to the host time upon specific VM life-cycle events, such as resuming from vMotion or a snapshot/consolidation.

Resolution

To disable all VMware Tools time synchronization, ensure that both periodic and one-off synchronization mechanisms are disabled. Disabling one-off time synchronization as described below will also automatically force disable periodic time synchronization.

Disable one-off time synchronization:

1. Open the VM settings in vCenter Server.
2. Navigate to VM Options.
3. Select VMware Tools.
4. Locate the Synchronize Time with Host configuration.
5. Deselect Synchronize at startup and resume (recommended).