NSX Host Node Tunnel Status is 'Degraded'

Products

• VMware NSX

Issue/Introduction

• 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:
  
  
  
  
  • Or shown that there was TEP down
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• The hosts in the Degraded state may also display an Alarm for "TEP Health":
  
  
  
  
• The tunnel status is displayed as down towards one of the Edge nodes or another ESXi transport node.
• Packet captures confirm that the host is transmitting BFD packets towards the other node.
• However, packet captures on the Edge uplinks/other node show that no packets are being received from the affected host.
• No port block conditions were observed on either the Edge or the ESXi host.

Environment

VMware NSX

Resolution

• Please try performing a manual “Sync Transport Node” on the affected host by Selecting the affected ESXi host > Click Actions > Choose “Sync Transport Node.”
• Verify whether any underlying physical infrastructure issues are present when packets appear to be exiting from the ESXi host.
• Validate the status of the remote transport node towards which the tunnels are down and ensure the other node is in UP state.
• In scenarios where the issue spans multiple ESXi hosts but is isolated to a single Edge, consider performing a reboot of the affected Edge.
• Review any third-party firewalls positioned between the impacted ESXi host and the Edge to ensure that there are no blocks or restrictions on BFD ports.

Additional Information

Refer below KB for additional steps of troubleshooting
Troubleshooting NSX TEP/BFD Tunnels between ESXi hosts and Edges