NSX-T Host Configuration Fails at 48% with Error: “Timeout waiting for host to join NSX Manager”

Products

• VMware NSX
• VMware vSphere ESXi

Issue/Introduction

• During ESXi host registration or NSX configuration on a standalone ESXi host, the configuration process fails at 48% with the following error on NSX Manager: 
  
  "Failed to install software on host. Time out waiting for host to join NSX Manager.".


• This issue occurs during the join phase, even though NSX VIB installation completes successfully on the ESXi host.
  
  
• In the VMware Cloud Foundation environment, the NSX deployment phase may fail with the below error:
  
  "Error in configuring VLAN backend transport node collections".


• On the ESXi host, in /var/log/nsx-syslog.log:
  
  YYYY-MM-DDTHH:MM:SSZ In(182) nsx-proxy[######] : NSX ###### - [nsx@#### comp="nsx-esx" subcomp="nsx-proxy" s2comp="nsx-net" tid="#####" level="INFO"] StreamSocket [##### Open f:53 i:0 ? -> ssl://<NSX-Manager-IP>:1234] on_connect 111-Connection refused
YYYY-MM-DDTHH:MM:SSZ Wa(180) nsx-proxy[######] : NSX ###### - [nsx@#### comp="nsx-esx" subcomp="nsx-proxy" s2comp="nsx-net" tid="#####" level="WARNING"] StreamConnection[##### Connecting to ssl://<NSX-Manager-IP>:1234 sid:#####] Couldnt connect to 'ssl://<NSX-Manager-IP>:1234' (error: 111-Connection refused)


• Testing port 1234 connectivity to the NSX Manager on ESXi fails:
  

  nc -zv <NSX-Manager-IP> 1234

  <NSX-Manager-IP> 1234 (tcp) open timed out

Environment

VMware NSX

VMware vSphere ESXi

VMware Cloud Foundation

Cause

The NSX configuration fails because the ESXi host cannot communicate with the NSX Manager over TCP port 1234, which is a mandatory requirement for completing the host registration.

Resolution

Ensure port 1234 is not blocked by firewall/NAT between the ESXi host and the NSX Manager. Port 1234 is used by NSX Manager Agent for incoming connections from the ESXi host during the join phase.

Additional Information

• Port TCP 1234 is required for standalone NSX deployments as well.

• Previously registered hosts might appear to work if their sessions are already established, but new hosts or re-registrations will fail without port access.