NSX-T Alert "Management Channel To Transport Node Down", "Management Channel To Transport Node Down Long" is reported in NSX Manager

Products

• VMware NSX-T Data Center

Issue/Introduction

• NSX-T Manager UI reports the Alarms as "Management Channel To Transport Node Down" or "Management Channel To Transport Node Down Long" 
• Host Transport nodes indicate NSX configuration of "Host Disconnected"
• Attempts to resolve Host Transport node Alarm "Host Disconnected" fail and remain in a disconnected state
• Ping attempts from Host transport node to NSX Manager IP are successful

  Management Channel To Transport Node Down
  This alarm is triggered when the messaging channel between the NSX Manager node and the Transport node remains down for a continuous period of 5 minutes

  Management channel to Transport node is down for too long.
  This alarm is triggered when the messaging channel between the NSX Manager node and the Transport node remains down for a continuous period of 15 minutes

Environment

VMware NSX-T Data Center

Cause

The MPA connectivity (port 1234) is down between the transport nodes and the manager.

Heartbeating between NSX management node and host is down

Resolution

Resolution: 

• Verify Network Connectivity: Ensure that MPA connectivity is permitted on port 1234 between the Transport Nodes and the NSX Manager.

• Test Port Communication: From the Host Transport Node CLI, run the following command to validate connectivity to the manager: nc -zv <NSX_Manager_IP/FQDN> 1234

• Check Service Status: On the NSX Manager nodes, verify that the messaging-manager service is active by executing: /etc/init.d/messaging-manager status

• Restart Service (If Required): If the service is reported as stopped or not running, restart it using the following command: /etc/init.d/messaging-manager restart

Additional Information

Reference documents:

Event Catalog

VMware NSX-T Data Center 3.2 Release Notes