NSX Host Validation Error 9544: Cannot update HostSwitch mode from STANDARD to ENS

Products

• VMware vSphere ESXi
• VMware NSX

Issue/Introduction

• When attempting to update a Transport Node Profile (TNP) or applying a configuration change to an NSX-prepared ESXi host, the Host Transport Node status shows  "Validation Error" in the NSX Manager UI with the following error message:

9544: Cannot update HostSwitch [UUID] Mode STANDARD to new Mode ENS. Please delete the HostSwitch and create it back with intended Mode. Please make the appropriate changes and reapply the configuration.

• Live vMotion failures between hosts in the same cluster with errors related to "different ENS modes."
• Inconsistent networking configuration across hosts within the same cluster (some hosts showing overlay segments, others showing only VLAN).

Environment

VMware NSX

Cause

This issue occurs because VMware NSX validation logic prevents the in-place conversion of a HostSwitch from STANDARD to ENS (Enhanced Data Path) mode while the host is actively prepared as a Transport Node.

Resolution

To resolve this error, the existing HostSwitch must be removed and recreated in the intended mode. This requires uninstalling and reinstalling NSX on the affected ESXi host by following the steps below:

1. Place Host in Maintenance Mode: In vCenter Server, right-click the affected ESXi host and select Maintenance Mode > Enter Maintenance Mode.

2. Uninstall NSX from the Host:

   • In the NSX Manager UI, navigate to System > Fabric > Hosts.
   • Select the affected host(s).
   • Click Actions > Remove NSX.
   • Note: If the host is part of a cluster managed by a Transport Node Profile, you may need to move the host out of the cluster temporarily to trigger the uninstallation.

3. Re-prepare the Host:

   • Move the host back into the NSX-enabled cluster (if it was moved out).
   • The Transport Node Profile should automatically begin the installation. Ensure the TNP is configured with the correct Host Switch Mode (Standard or Enhanced Datapath) as required.
   • If not automated, select the host and click Configure NSX.

4. Verify Status: Monitor the installation in the NSX Manager UI. The status should transition to Success and the configuration state to Up.

5. Exit Maintenance Mode: Once the configuration is successful, exit maintenance mode and migrate VMs back to the host.

Additional Information

Enhanced Data Path Requirements