Error: ESXi host transport node disconnected with loss of heartbeat in NSX

Products

• VMware NSX
• VMware vSphere ESXi

Issue/Introduction

• Host transport nodes show a status of "Host Disconnected" or "Powered off".
  
  
  
• Heartbeating between NSX management node and host XXXXX is down error. 
  
• Clicking the Resolve button may not immediately clear the status if certificates are out of sync.

Environment

VMware NSX 3.X / 4.X

VMware ESXi 7.X / 8.X

Cause

The NSX Manager sends heartbeats every minute to host transport nodes. If heartbeats are not received, the manager marks the host as disconnected. Common causes include:

• Expired or mismatched APH/Host certificates.
• Network connectivity issues on management ports.
• Unresponsive nsx-proxy services on the ESXi host.

Resolution

There are multiple reasons for a host to show as disconnected in the NSX UI, ranging from certificate issues to network reachability problems.

1. Verify network reachability between the NSX Manager and the ESXi host management interface.
2. Check for any VLAN or routing issues in the physical network.
3. Navigate to System > Fabric > Nodes > Host Transport Nodes.
4. Expand the affected cluster and identify hosts with Host Disconnected status.
5. Click Host Disconnected and select Resolve to re-sync thumbprints and certificates.
6. If the issue persists, log in to the ESXi host via SSH and check the proxy status: /etc/init.d/nsx-proxy status
7. Restart the service if it is unresponsive: /etc/init.d/nsx-proxy restart
8. For expired certificates, use the Certificate Analyzer, Results and Recovery (CARR) script (Reference: KB 369034).

Additional Information

These are some of the issues that may result in a host showing as disconnected in the NSX UI.

• "Waiting for MPA" error after ESX 7.x Host upgrade from NSX 4.2.1.0 to a version less than 4.2.3 gets stuck at 45%
• Host or Edge Transport Nodes disconnected from NSX UI after NSX managers were restored from backup
• ESXi Hosts's NSX Configuration status shows Host Disconnected in NSX UI
• NSX Certificate Expired Alarm

The latest download are available at Broadcom downloads.For more information, see Creating and managing Broadcom support cases.