HCX Interconnect (IX) and Network Extension (NE) Tunnels Report as "Down" in VCF environment.

Products

• VMware HCX

Issue/Introduction

• In a VMware Cloud Foundation (VCF) environment, both the HCX Interconnect (IX) and Network Extension (NE) tunnels are reporting their status as "Down." 
  
  
  
  
•  Executing the ccli list command from the HCX Manager displays the fleet appliances (IX/NE) in a "Disconnected" state.
  
  
  
  
  
• This indicates a management communication failure between the HCX Manager and the IX/NE appliances.
  
  
• A review of the HCX Manager logs (/common/admin/logs/app.log) shows that the Manager cannot communicate with the fleet appliances, reporting a No route to host (Host unreachable) error over port 9443 (the internal port used for HCX Manager to IX/NE appliance communication).
  
  Example Log Excerpt (app.log):
  
  2026-06-19 06:48:12.489 UTC [InterconnectService_SvcThread-2079, IX:######-#####-####-####-#######, J:2a188b16, , TxId: #####-#####-#####-#######] ERROR c.v.v.h.a.gateway.GatewayAdapter- Error occurred while executing GET on https://##.##.##.##9443/ha/state. Error: {}
java.net.NoRouteToHostException: No route to host (Host unreachable)
  
  
• Despite the "No route to host" error, the HCX Manager and the IX/NE appliances are deployed on the exact same Layer 2 network. Because no Layer 3 routing is actually involved between these components, this error points to a localized Layer 2 connectivity break rather than a routing failure.

Environment

HCX 4.11.x

Cause

This issue occurs when IX/NE appliances are deployed on, or migrated to ESXi hosts in the Workload Domain that do not have the required VLAN configured on their vSphere Distributed Switch (VDS) port groups. The missing VLAN configuration results in a Layer 2 connectivity lost between the HCX Manager in the Management Domain and the IX/NE virtual machines running on the affected Workload Domain hosts.

Resolution

To resolve this issue, the missing management network configuration must be applied to the newly added ESXi hosts within the worker domain.

1. Access the Worker Node vCenter Web Client and navigate to the networking settings for the affected ESXi hosts.

2. Configure the missing VLAN (along with any other requisite HCX networks) on the appropriate distributed virtual switches or port groups. This ensures the new hosts match the network configuration of the rest of the deployment cluster.

3. Once the VLAN is correctly configured, verify that Layer 2 management communication is restored between the HCX Manager and the IX/NE appliances.

4. Open the HCX Dashboard and confirm that the IX and NE tunnel statuses have successfully returned to "Up."