NSX-T Virtual Machines tags are deleted when ESXi hosts disconnect from vCenter

Products

• VMware NSX Networking

Issue/Introduction

Symptoms:

• NSX-T version is 2.4.x or 2.5.x
• NSX Manager logs (syslog.log) display message(s) indicating ESXi host disconnected from vCenter, similar to:

<182>1 2020-04-15T15:18:13.379Z vli0esx801 NSX 8325 SYSTEM [nsx@6876 comp="nsx-manager" subcomp="Fabric"] HostSystem update on cmId 6dd8e89a-1b30-4bb2-b7cf-XXXX -> HostSystem [id=host-8888, runtime.connectionState=notResponding, runtime.powerState=unknown]

Environment

VMware NSX-T Data Center 2.x
VMware NSX-T Data Center

Cause

When an ESXi host is disconnected from vCenter the Virtual Machine object are deleted and re-created with new instance uuid.
Since the NSX-T VM tags are also associated with the instance uuid, the tags are not applied to the re-created VMs.

Resolution

This issue is resolved in NSX-T 3.0.

Workaround:
To workaround the issue, reconnect the ESXi to vCenter or re-create the VM tags manually.

Additional Information

Impact/Risks:
This issue could result in Distributed Firewall Rules to stop been applied if the rules are using NSGroup with membership criteria based on the VM tags.