Dummy Opaque Networks Persist After Migrating VMs from vCenter with NSX to vCenter without NSX

Products

• VMware NSX
• VMware NSX-T Data Center

Issue/Introduction

• After migrating VMs from a vCenter with NSX to a vCenter without NSX, dummy opaque networks with the type "nsx.logicalswitch" gets created in the destination vCenter.
• In the destination vCenter, navigate to the Networking section and observe dummy opaque networks with the type "nsx.logicalswitch".
• Check the VMs' vNIC configurations and verify that they are connected to a different network segment.

Environment

VMware NSX

VMware NSX-T Data Center

 

Cause

The issue occurs because the VMs still have snapshots that reference the legacy NSX opaque network in their configuration files (VMX). These references cause the vCenter to populate dummy opaque networks even though NSX is not present in the new environment.

Resolution

This is a known issue impacting VMware NSX

Workaround:

1. Identify and remove all snapshots of VMs that contain references to the legacy opaque networks.
2. Once the snapshots are deleted, the dummy opaque networks will no longer be populated in the destination vCenter.

Additional Information

Ensure that before removing snapshots, any critical data is preserved or backed up.