In NSX Data Center, you can diagnose the overall health status of the host. The overall host health status includes the host pNIC status, tunnel status, the connectivity status between the host and the control plane, and the connectivity status between the host and the management plane.

You can monitor the host health status only by using the NSX APIs. This diagnostic feature is not available in the vCenter UI.

The host health status includes the following substatuses:
  • pNIC status
  • Tunnel status
  • Control plane status
  • Management plane status

The following table describes each of these substatuses.

Substatus Description
pNIC status
This status is derived from the physical layer. When the pNICs belong to a link aggregation group (LAG), the status is either Up, Down, or Degraded.
  • When all the pNICs in the LAG are up, the LAG status is Up.
  • When all the pNICs in the LAG are down, the LAG status is Down.
  • If any one of the pNICs in the LAG is down, the LAG status is Degraded.

When the pNIC does not belong to a LAG, the status is either Up or Down.
Tunnel status
It is the connectivity status of the VTEP to VTEP tunnel between the hosts. The tunnel status is either Up, Down, or Degraded.
  • When all the tunnels of the hosts are up, the tunnel status is Up.
  • When all the tunnels of the hosts are down, the tunnel status is Down.
  • When any one of the tunnels of the hosts is down, the tunnel status is Degraded.
Control plane status

It is the connection status between the host and the NSX Controllers.
Management plane status

It is the connection status between the host and the NSX management plane.

The management plane determines the overall status of the host as follows:
  • When all the substatuses are up, the overall host status is Up.
  • When any substatus is down, the overall host status is Down.
  • When at least one of the substatuses is degraded, and the other substatuses are up or down, the overall host status is Degraded.

Activate Host Health Status Monitoring

To activate monitoring of the host health status, you must enable global pNIC status check on the hosts and global Bidirectional Forwarding Detection (BFD). Run the following PUT APIs:
Enable global pNIC status check on hosts
PUT <NSX_Manager_IP>/api/2.0/vdn/pnic-check/configuration/global
Enable global BFD
PUT <NSX_Manager_IP>/api/2.0/vdn/bfd/configuration/global

In NSX 6.4.6 or earlier, when you enable global BFD, the monitoring of tunnel latency and tunnel health is enabled simultaneously. You cannot separately turn on or turn off the monitoring of tunnel latency and tunnel health.

Starting in NSX 6.4.7, global BFD configuration API includes two additional parameters to enable or disable the monitoring of tunnel health and tunnel latency separately.

When BFD is disabled, tunnel latency and tunnel health monitoring cannot be turned on. When BFD in enabled, you can individually enable the monitoring of tunnel health and tunnel latency. This decoupling provides greater flexibility and avoids performance problems when the number of hosts scale in the network.

For a detailed information about configuring the global BFD parameters, see the NSX API Guide.

View Host Health Status

To diagnose the host health status and the tunnel details, you can run the following APIs:
  • GET <NSX_Manager_IP>/api/2.0/vdn/pnic-check/configuration/global
  • GET <NSX_Manager_IP>/api/2.0/vdn/host/status
  • GET <NSX_Manager_IP>/api/2.0/vdn/host/{hostId}/status
  • GET <NSX_Manager_IP>/api/2.0/vdn/host/{hostId}/tunnel
  • GET <NSX_Manager_IP>/api/2.0/vdn/host/{hostId}/remote-host-status

For a detailed information about each of these APIs, including the parameter description and the API response example, see the NSX API Guide.