vSphere Client UI Error Cannot read properties of null reading qosTagValue on VDS Portgroups

Products

• VMware vCenter Server
• VMware vSphere ESXi

Issue/Introduction

When attempting to edit the Traffic Marking properties of an existing Distributed Virtual Switch (VDS) Portgroup via the vSphere Client UI, the following error is displayed:

TypeError: Cannot read properties of null (reading 'qosTagValue')

Additionally, packet captures on the ESXi host confirm that QoS tags are not being applied to the ingress traffic flow.

Environment

VMware vSphere

Cause

The traffic marking rules were deployed via a custom PowerShell script that lacked the specific metadata structure expected by the UI. This resulted in a null property flag in the script-created rule, which prevented QoS tags from being applied to the traffic and caused the UI to fail when attempting to read the missing property.

Resolution

• Delete the faulty script-created rule on the affected test or production portgroups.

• Activate vSphere Code Capture in the Developer Center.

• Manually configure and recreate the traffic marking rule via the vSphere Client UI (e.g., Ingress only traffic with CoS tag 1 and DSCP tag 8).

• Download the resulting script output from Code Capture to capture the correct API schema.

• Review the downloaded Code Capture script to identify schema discrepancies and update the custom PowerShell script accordingly to prevent future occurrences.

Additional Information

It is recommended to deploy a test VM on the remediated portgroup and perform a packet capture to verify that the manually created rules are applying the QoS tags correctly.