NSX Manager shows ESXi host Degraded status after TEP migration to Static IP Pool.

Products

• VMware NSX

Issue/Introduction

After transitioning ESXi Tunnel Endpoints from DHCP to a Static IP Pool in VMware NSX, several hosts across clusters may report a Degraded status in the NSX UI. This is typically accompanied by Tunnel Down errors with multiple peer TEPs.

While the UI indicates a failure, network connectivity is often functional, as evidenced by successful ICMP pings between affected TEP IPs. This suggests a management-plane synchronization delay or stale session states rather than a functional data path failure.

 

Environment

VMware NSX

Cause

The "Degraded" status results from the NSX management plane failing to resynchronize session states quickly after a shift in TEP IP assignments, especially if a duplicate IP segment issue occurred during the transition. Stale entries in the ARP tables or BFD session states prevent tunnels from re-establishing automatically despite functional physical connectivity.

The vmkernel.log on the ESXi host contained entries stating: 'BFD local vtep segment is same as remote vtep segment #.#.#.#' 

 

Resolution

To restore the tunnel status and synchronize the management plane.

Manual Sync: Attempt a manual synchronization for the impacted transport nodes from the NSX UI

• One or more transport nodes appear in a Degraded state when viewed in the NSX UI under Fabric > Hosts.
• The hosts in the Degraded state may display the "Out of Sync" error:
  
  

Additional Information

If the status remains Degraded, place the impacted ESXi host into Maintenance Mode. In some scenarios, entering Maintenance Mode alone triggers the necessary synchronization to restore tunnel status.